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Talazoparib, BMN 673

February 8, 2016 7:25 am / Leave a comment

Talazoparib, BMN-673, MDV-3800

(2S,3S)-methyl-7-fluoro-2-(4-fluorophenyl)-3-(1-methyl-1H-1,2,4-triazol-5-yl)-4-oxo-1,2,3,4-tetrahydroquinoline-5-carboxylate

(8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-de]phthalazin-3(7H)-one

(8S,9R)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one

CAS 1207456-01-6
Chemical Formula: C19H14F2N6O
Exact Mass: 380.11972

BMN673, BMN673, BMN-673, LT673, LT 673, LT-673, Talazoparib

BioMarin Pharmaceutical Inc

phase 3

Poly ADP ribose polymerase 2 inhibitor; Poly ADP ribose polymerase 1 inhibitor

cancer

(85,9R)-5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-de]phthalazin-3(7H)-one toluenesulfonate salt

CAS 1373431-65-2(Talazoparib Tosylate)

1H NMR DMSOD6

str1

13C NMR DMSOD6

str1

HMBC NMR

str1

HSQC NMR

str1

Talazoparib (BMN-673) is an investigational drug that acts as a PARP inhibitor. It is in clinical trials for various cancers.

Medivation, under license from BioMarin Pharmaceuticals, following its acquisition of LEAD Therapeutics, is developing a PARP-1/2 inhibitor, talazoparib, for treating cancer, particularly BRCA-mutated breast cancer. In February 2016, talazoparib was reported to be in phase 3 clinical development

Talazoparib, also known as BMN-673, is an orally bioavailable inhibitor of the nuclear enzyme poly(ADP-ribose) polymerase (PARP) with potential antineoplastic activity (PARP1 IC50 = 0.57 nmol/L). BMN-673 selectively binds to PARP and prevents PARP-mediated DNA repair of single strand DNA breaks via the base-excision repair pathway. This enhances the accumulation of DNA strand breaks, promotes genomic instability and eventually leads to apoptosis. PARP catalyzes post-translational ADP-ribosylation of nuclear proteins that signal and recruit other proteins to repair damaged DNA and is activated by single-strand DNA breaks. BMN-673 has been proven to be highly active in mouse models of human cancer and also appears to be more selectively cytotoxic with a longer half-life and better bioavailability as compared to other compounds in development. Check for active clinical trials or closed clinical trials using this agent.

Talazoparib is C₁₉H₁₄F₂N₆O.

Talazoparib tosylate is C₂₆H₂₂F₂N₆O₄S.^[1]

Approvals and indications

None yet.

Mechanism of action

Main article: PARP inhibitor

Clinical trials

After trials for advanced hematological malignancies and for advanced or recurrent solid tumors.^[2] it is now in phase 3 for metastatic germline BRCA mutated breast cancer.^[3] Trial estimated to complete in June 2016.^[4]

As of January 2016 it in 14 active clinical trials.^[5]

WO2010017055, WO2015069851, WO 2012054698, WO 2011130661, WO 2013028495, US 2014323725, WO 2011097602

PAPER

Discovery and Characterization of (8S,9R)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one (BMN 673, Talazoparib), a Novel, Highly Potent, and Orally Efficacious Poly(ADP-ribose) Polymerase-1/2 Inhibitor, as an Anticancer Agent

Bing Wang^*, Daniel Chu, Ying Feng, Yuqiao Shen, Mika Aoyagi-Scharber, and Leonard E. Post

BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, California 94949, United States

J. Med. Chem., 2016, 59 (1), pp 335–357

DOI: 10.1021/acs.jmedchem.5b01498

Publication Date (Web): December 10, 2015

*Phone: 1-415-506-3319. E-mail: bwang@bmrn.com.

Abstract

We discovered and developed a novel series of tetrahydropyridophthlazinones as poly(ADP-ribose) polymerase (PARP) 1 and 2 inhibitors. Lead optimization led to the identification of (8S,9R)-47 (talazoparib; BMN 673; (8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one). The novel stereospecific dual chiral-center-embedded structure of this compound has enabled extensive and unique binding interactions with PARP1/2 proteins. (8S,9R)-47 demonstrates excellent potency, inhibiting PARP1 and PARP2 enzyme activity with K_i = 1.2 and 0.87 nM, respectively. It inhibits PARP-mediated PARylation in a whole-cell assay with an EC₅₀ of 2.51 nM and prevents proliferation of cancer cells carrying mutant BRCA1/2, with EC₅₀ = 0.3 nM (MX-1) and 5 nM (Capan-1), respectively. (8S,9R)-47 is orally available, displaying favorable pharmacokinetic (PK) properties and remarkable antitumor efficacy in the BRCA1 mutant MX-1 breast cancer xenograft model following oral administration as a single-agent or in combination with chemotherapy agents such as temozolomide and cisplatin. (8S,9R)-47 has completed phase 1 clinical trial and is currently being studied in phase 2 and 3 clinical trials for the treatment of locally advanced and/or metastatic breast cancer with germline BRCA1/2 deleterious mutations.

http://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.5b01498

http://pubs.acs.org/doi/suppl/10.1021/acs.jmedchem.5b01498/suppl_file/jm5b01498_si_001.pdf

Preparation of (8S,9R)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one Tosylate Salt ((8S,9R)-47 Tosylate Salt)

A suspension of (8S,9R)-47 (BMN 673) (400 mg, 1.05 mmol) in a mixture of acetone (27 mL) and THF (13 mL) was heated to reflux until the suspension became clear. TsOH (220 mg, 1.16 mmol) was then added to the solution. White solids started to precipitate out from the solution shortly after the addition of TsOH. After stirring at 25 °C for 30 min, the mixture was filtered to collect the white crystal solids, which were washed with a mixture of acetone (10 mL) and 1,4-dioxane (4 mL) and then dried under vacuum at 45 °C for 3 days. This afforded the product as a white crystalline solid (540 mg, yield 93%). ¹H NMR (400 MHz, DMSO-d₆) δ (ppm) 2.29 (s, 3H), 3.67 (s, 3H), 4.97–5.06 (m, 2H), 6.91–6.94 (dd, J₁ = 2.0 Hz, J₂ = 10.8 Hz, 1H), 7.06–7.19 (m, 5H), 7.19–7.51 (m, 4H), 7.74 (s, 1H), 7.87 (s, 1H), 10.32 (brs, 1H), 12.36 (s, 1H). LC-MS (ESI)m/z: 381 (M + H)⁺. Anal. Calcd for C₁₉H₁₄F₂N₆O·toluene sulfonic acid: C, 56.52; H, 4.01; N, 15.21. Found: C, 56.49; H, 3.94; N, 15.39.

(8S,9R)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one (8S,9R)-47 or BMN 673 and (8R,9S)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one (8R,9S)-47

Compound 47 was dissolved in DMF, and chiral resolution was performed using supercritical-fluid chromatography (SFC) with a CHIRALPAK IA chiral column and methanol (20% with 0.1% DEA) and CO₂ (80%) as the eluents. Yield 90%. For (8S,9R)-47 (BMN 673): retention time 8.8 min and ee 99.3%. For (8R,9S)-47: retention time 10.2 min and ee 99.2%.

Alternatively, compound (8S,9R)-47 could also be made using (2S,3R)-60a as a starting material and employing the same procedure described for the conversion of 60a to 47.

The optical rotation for both (8S,9R)-47 and (8R,9S)-47 was measured using a RUDOLPH (AUTOPOL V) automatic polarimeter at a concentration of 6.67 mg/mL in MeOH/MeCN/DMF = 0.5:0.5:1 at 20 °C. The specific rotation for (8S,9R)-47 was +92.2°, whereas it was −93.4° for (8R,9S)-47.

PATENT

WO-2016019125

WO2016019125

The compound (85,9R)-5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-de]phthalazin-3(7H)-one toluenesulfonate salt (Compound (A))

Compound (A)

is an inhibitor of poly(ADP-ribose)polymerase (PARP). Methods of making it are described in WO2010017055, WO2011097602, and WO2012054698. However, the disclosed synthetic routes require chiral chromatography of one of the synthetic intermediates in the route to make Compound (A), methyl 7-fluoro-2-(4-fluorophenyl)-3-(l -methyl- lH-1, 2,4-triazol-5-yl)-4-oxo- 1 ,2,3,4-tetrahydroquinoline-5-carboxylate (Intermediate (A)),

Intermediate (A)

to yield the chirally pure (2S,35)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH- 1,2,4-triazol-5-yl)-4-oxo-l,2,3,4-tetrahydroquinoline-5-carboxylate (Compound (1))

Compound (1).

Using conventional chiral chromatography is often solvent and time intensive.

Use of more efficient chromatography methods, such as simulated moving bed (SMB) chromatography still requires the use of expensive chiral chromatography resins, and is not practical on a large scale to purify pharmaceutical compounds. Also, maintaining

Compound (1) in solution for an extended time period during chromatography can lead to epimerization at the 9-position and cleavage of the methyl ester group in Compound (1). Replacing the chromatography step with crystallization step(s) to purify Compound (1) is desirable and overcomes these issues. Therefore, it is desirable to find an alternative to the use of chiral chromatography separations to obtain enantiomeric Compound (1).

Scheme 1 below describes use of Ac49 as a coformer acid for the preparation of Compound (la) and for the chiral resolution of Compound (1).

Scheme 1

Compound (1 )

Example 2 – Preparation of Compound (1) Using Scheme 1

Step la

Intermediate (A) (5 g, 12.5 mmol) was dissolved in 9: 1 v/v MIBK/ethanol (70 mL, 14 vol.) at 50 °C with stirring and dissolution was observed in less than about 5 minutes. [(lS)-en<io]-(+)-3-bromo-10-camphor sulfonic acid monohydrate (4.1 g, 12.5 mmol) was added and dissolution was observed in about 10-20 minutes. Seeding was then performed with Compound (la) (95% e.e., 5 mg, 0.1% w.) and the system was allowed to equilibrate for about 1 hour at 50 ^°C, was cooled to about 20 °C at 0.15 °C/min, and then equilibrated at 20 °C for 2 hours. The solid phase was isolated by filtration, washed with ethanol, and dried at about 50 °C and 3 mbar for about 2 to 3 hours to yield Compound (la) as a 0.6 molar equiv. EtOH solvate and 0.6 molar equiv. hydrate (93.4% e.e.).

Step lb

Compound (la) was then suspended in MIBK/ethanol 95/5% by volume (38 mL, 10 vol.) at 50 °C with stirring. After about 2 hours at 50 °C, the suspension was cooled to about 5 °C for 10 to 15 hours. The solid phase was recovered by filtration and dried at about 50 °C and 3 mbar for about 3 hours. Compound (la) (97.4% e.e.) was recovered. Step 2

000138] Compound (1) was released by suspending Compound (la) (3.9 g, 5.5 mmoi), without performing the optional reslurrying in Step 1, in 20 mL of water at room temperature and treating with 5M sodium hydroxide in water (1.3 mL, 1.2 mol). The mixture was kept at room temperature for about 15 hours and the solid was isolated by filtration and dried at 50 °C and 3 mbar for about 3 hours. Compound (1) was recovered (94.4% e.e.).

Example 3 – Large Scale Preparation of Compound (1) Using Scheme 1

The procedure of Example 1 was followed using 3.3 kg of Intermediate (A) and the respective solvent ratios to provide 95.7% e.e. in Step la; 99.2% e.e. in Step lb; and 99.2% e.e. in Step 2.

Example 4 – Alternative Preparation of Compound (1) Using Scheme 1

Step la

Intermediate (A) (751 mg, 1.86 mmol)) was dissolved in 9: 1 v/v

MIBK/ethanol (7.5 mL, 10 vol.) at 50 °C with stirring. [(15)-eni o]-(+)-3-bromo-10-camphor sulfonic acid monohydrate (620 mg, 1.88 mmol, 1 equiv.) was added. Formation of a precipitate was observed at about 1 hour at 50 °C. The system was then cooled to about 5 °C at 0.1 °C/min, and then equilibrated at 5 °C for about 60 hours. The solid phase was isolated by filtration and dried at about 50 °C and 3 mbar for about 2 hours to yield

Compound (la)(92% e.e.). See Figures 1-4 for XRPD (Figure 1), chiral HPLC (Figure 2), Ή NMR (Figure 3), and TGA/DSC analyses (Figure 4). The XRPD pattern from the material in Example 3 is similar to that in Example 1 with some slight shifts in the positions of specific diffraction peaks (highlighted by black arrows in Figure l). The ‘H NIVIR was consistent with a mono-salt of Compound (la) containing 0.5 molar equivalent of EtOH and 0.6% by weight residual MIBK. The TGA analysis showed a stepwise mass loss of 3.5% between 25 and 90 °C (potentially representing loss of the 0.5 molar equivalent of EtOH) and a gradual mass loss of 1.2% between 90 and 160 °C (potentially representing the loss of adsorbed water). The DSC analysis had a broad endotherm between 25 and 90 °C

representing desolvation and an endotherm at 135 °C representing melt/degradation.

Step lb

Compound (la) (100.3 mg, 0.141 mmol) was re-suspended in 95:5 v/v MIBK EtOH (1 mL, 10 vol.) at 50 °C and stirred for 1 hour before cooling to 5 °C at

0.1 °C/min. The solid (99.4% e.e.) was recovered by filtration after 1 night at 5 °C. Shifts in the XRPD diffraction peaks were no longer detected (Figure 5; compare Figure 1). Figure 6 shows the chiral HPLC for Compound (la).

Step 2

Compound (la) (100.2 mg, 0.141 mmol) from Step la was suspended in water (2 mL, 20 vol.) at 50 ^°C and 5 M NaOH in water (34 μL·, 1.2 molar equiv) was added. The resulting suspension was kept at 50 °C for one night, cooled to room temperature

(uncontrolled cooling) and filtered to yield Compound (1) (92% e.e.). The chiral purity was not impacted by this step and no [(15)-enJo]-(+)-3-bromo-10-camphor sulfonic acid was detected by NMR. Figure 7 compares the XRPD of Compound (1) in Step 2 with

Intermediate (A), the starting material of Step 1. Figure 8 shows the NMR of Compound (1) in Step 2 with Intermediate (A), the starting material of Step 1.

Example 5 – Alternative Preparation of Compound (1) Using Scheme 1 Step la

000144] Intermediate (A) (1 equiv.) was added with stirring to a solution of MIBK (12-13 vol), ethanol (1-1.5 vol), and water (0.05-0.10 vol) and the reaction was heated within 15 minutes to an internal temperature of about 48 °C to about 52 °C . [(lS)-endo]-(+)-3-bromo- 10-camphor sulfonic acid (1 equiv) was added and the reaction was stirred for about 5-10 mins at an internal temperature of about 48 °C to about 52 °C until dissolution occurred. Seed crystals of Compound (la) were added and the reaction was allowed to proceed for 1 hour at an internal temperature of about 48 °C to about 52 °C. The reaction was cooled at a rate of 0.15 °C /min to about 19-21 °C. The suspension was stirred for 2 hours at an internal temperature of about 19 °C to 21 °C and then was collected by filtration and washed twice with ethanol. The product was characterized by 1H NMR and ¹³C NMR (Figures 13a and 13b), IR Spectrum (Figure 14), DSC (Figure 15), and chiral HPLC (Figure 16).

Step 2a

To Compound (la) (1 equiv.) was added acetone (1.1 vol), IPA (0.55 vol), and methanol (0.55 vol) and the reaction was heated to an internal temperature of about 38 °C to 42 °C. Aqueous ammonia (25%) (1.3 equiv) was added and the reaction was stirred for about 10 minutes. The pH of the reaction was confirmed and the next step performed if > 7. Water was added (0.55 vol), the reaction was cooled to an internal temperature of about 35 °C, seed crystals of Compound (1) were added, and the reaction was stirred for about 10 mins. Water was added (3.3 vol) dropwise within about 30 minutes, the suspension was cooled within 30 minutes to an internal temperature of about 0 °C to 5 °C, and the reaction was stirred for 15 minutes. The solid was collected by filtration and washed three times with water.

Step 2b

To the product of Step 2a) was added acetone (4 vol), ΓΡΑ (1 vol), and methanol (1 vol) and the reaction was heated to an internal temperature of about 38 °C to 42 °C resulting in a clear solution. Water (2 vol) and seed crystals of Compound (1) were added and the system was stirred for about 15 minutes at an internal temperature of about 35 °C. Water (342 mL) was added dropwise in about 30 minutes. The suspension was then cooled in 30 min to an internal temperature of about 0 °C to 5 °C and was stirred for an additional 15 minutes. The solid was collected by filtration, washed twice with water, and chiral purity was determined. If > 99% e.e., then the solid was dried at an internal temperature of about 60 °C under reduced pressure to yield Compound (1). The product was characterized by Ή NMR (Figure 19), ¹³C NMR (Figure 20), IR (Figure 21), DSC (Figure 22), chiral HPLC (Figure 23).

Scheme 2 below describes use of Acl 10 as a coformer acid for the preparation of Compound (lb) and the chiral resolution of Compound (1).

Intermediate (A)

Compound (1 b)

Intermediate (A)

Compound (1 b)

Compound (1 )

Example 6 – Preparation of Compound (1) Using Scheme 2

Step la

Intermediate (A) (102 mg, 0.256 mmol) was dissolved in MIBK (1 mL, 10 vol.) at 65 ^°C with stirring. (lS)-phenylethanesulfonic acid, prepared using procedures known to one of skill in the art, in MIBK (3.8 M, 80 μί, 1 molar equiv.) was added and a suspension was observed after 30 minutes at 65 °C. The system was kept at 65 °C for another 30 minutes before cooling to 5 ^°C at 0.1 C/min. After one night at 5 °C, the solid was filtered, dried at 50 °C, 3 mbar pressure for about 2 hours to yield Compound (lb). See Figures 9-12 for XRPD (Figure 9), chiral HPLC (Figure 10), Ή NMR (Figure 11), and TGA/DSC analyses (Figures 12a and 12b). The XRPD diffraction pattern of the solid obtained in Example 5 differed from the XRPD pattern obtained with the solid from in the salt screen of Example 1 and was consistent with the production of different solids in Examples 1 and 5. The Ή NMR was consistent with the mono-salt with a 0.3% by weight residue of dioxane. In Figure 12a, the thermal behavior was consistent with a non-solvated form exhibiting a melt/degradation at 201 °C. Figure 12b compares the melt pattern of Compound (lb) in Example 5 with Compound (lb) in Example 1.

Steps lb and 2 can be carried out using procedures similar to those used in Examples 2-5.

Example 7 – Polymorphism of Compound (la)

Compound (1) (92% e.e., 10 mg, mmol) was placed in 1.5 mL vials and the solvents (1 mL or less) of Table 3 were added at 50 °C until dissolution was achieved. [(1S)-eni o]-(+)-3-bromo-10-camphorsulfonic acid was added as a solid at 50 °C. The samples were kept at 50 °C for about 1 hour prior to being cooled to room temperature overnight

(uncontrolled cooling rate). Clear solutions were successively cooled to 4 °C, -20 °C and evaporated at room temperature. Any gum obtained after evaporation was re-suspended in diethyl ether. The solid phases generated were characterized by XRPD and if relevant, by Ή NMR and TGA/DSC.

Table 3. Compound (la) Polymorphism Conditions

C.S. means clear solution and Susp. means suspension. “A” means the XRPD diffraction pattern was new but similar to that for Ac49 in

Example 1. “B” means the XRPD diffraction pattern was the same as that for Ac49 in Example 1. “M.E.” means molar equiv.

Page 38 of 64

NAI- 1500460480V I

Each of the seven solvents in which solvates were observed (heterosolvates not included) were mixed with MIBK (90% vol). Solutions of Intermediate (A) were prepared in the solvent mixtures (10 vol) at 50 C and [(15)-en<io]-(+)-3-bromo-10-camphor sulfonic acid (1 molar equivalent) was added. The resulting clear solutions were cooled to 5 °C at 0.2 C/min. Surprisingly, no crystallization was reported in any sample. Seeding was performed with a few crystals of each solvate at about 25 °C. The solid phases were analyzed by XRPD and the liquid phases were analyzed by chiral HPLC. See Table 4 for a summary of the results (where “Dias 2” is the (2R, 3R) diastereomer of Compound (la)) .

Table 4. Compound (la) Solvate Analysis

As seen in Table 4 above, the ethanol/MIBK system yielded 93% pure Compound (la) which demonstrates that Compound (la) does crystallize in a very pure form as an ethanolate solvate.

Other objects, features and advantages of the compounds, methods and compositions described herein will become apparent from the following description. It should be understood, however, that the description and the specific examples, while indicating specific embodiments, are given by way of illustration only, since various changes and modifications within the spirit and scope of the present description will become apparent from this detailed description.

All publications including patents, patent applications and published patent applications cited herein are hereby incorporated by reference for all purposes.

PATENT

US 2011196153

http://www.google.co.ve/patents/US20110237581

Patent

US 2011237581

PATENT

http://www.google.com/patents/WO2015069851A1?cl=en

SYNTHETIC EXAMPLES

Example 1

\ ,

(1 a) (2) (3) (la) (5)

To a flask was added N-methyl-l,2,4-triazole (la)(249.3 g, 3.0 mol, 1 equiv.),

2-methyl-THF (1020 mL, about 1 :4 m/v), and DMF (2)(230.2 g, 3.15 mol, 1.05 equiv.), in any order. The solution was cooled to an internal temperature of about -5 to 0 °C. To the flask was added LiHMDS (3) as a 20% solution in 2-methyl-THF (3012 g, 3.6 mol, 1.2 equiv.) dropwise within about 60 minutes. During the addition of the LiHMDS (3), the desired Compound (la) was precipitated as the 2-methyl-THF solvate, and the flask was cooled to about -30 °C. The reaction was stirred for about 30 minutes at an internal temperature of about -5 to 0 °C.

The precipitated crystals were removed from the reaction mixture by filtration and washed with 2-methyl-THF. The product, Compound (la) as the 2-methyl-THF solvate, was dried under vacuum at an internal temperature of about 60 °C (about 72.5% as measured by NMR) to yield Compound (la).

Example 2

As shown in Example 2, the Compounds of Formula I are useful in the synthesis of more complex compounds. See General Scheme 1 for a description of how the first step can be accomplished. Compounds of Formula I can be reacted with compound (6) to yield Compounds of Formula II. In Example 2, Compound (la) can be reacted with

Compound (6) to yield Compound (7). The remaining steps are accomplished using procedures known to one of ordinary skill in the art, for example, as disclosed in

WO2010017055 and WO2011097602 to yield Compound (12).

PATENT

US 2014323725/http://www.google.com/patents/WO2011097602A1

5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-yl)-8,9- dihydro-2H-pyrido[4,3,2-Je]phthalazin-3(7H)-one, as shown in formula (1), and its enantiomer compounds, as shown in formulas (la) and (lb):

Example 1

(Z)-6-Fluoro-3-(( 1 -methyl- IH- 1 ,2,4-triazol-5 -yl)methylene)-4-nitroisobenzofuran- 1 (3H)-one (3)

[0053] To a 80 L jacketed glass reactor equipped with a chiller, mechanical stirrer, thermocouple, and nitrogen inlet/outlet, at 15 – 25 °C, anhydrous 2-methyl-tetrahydrofuran (22.7 kg), 6-fluoro-4- nitroisobenzofuran-l(3H)-one (2) (2.4 kg, 12.2 mol, 1.00 eq.), and 2-methyl-2H-l,2,4-triazole-3- carbaldehyde (49.6 – 52.6 % concentration in dichloromethane by GC, 3.59 – 3.38 kg, 16.0 mol, 1.31 eq.) were charged consecutively. Triethylamine (1.50 kg, 14.8 mol, 1.21 eq.) was then charged into the above reaction mixture. The reaction mixture was stirred for another 10 minutes. Acetic anhydride (9.09 – 9.10 kg, 89.0 – 89.1 mol, 7.30 eq.) was charged into the above reaction mixture at room temperature for 20 – 30 minutes. The reaction mixture was heated from ambient to reflux temperatures (85 – 95 °C) for 80 – 90 minutes, and the mixture was refluxed for another 70 – 90 minutes. The reaction mixture was monitored by HPLC, indicating compound (2) was reduced to < 5 %. The resulting slurry was cooled down to 5 – 15 °C for 150 – 250 minutes. The slurry was aged at 5 – 15 °C for another 80 – 90 minutes. The slurry was filtered, and the wet cake was washed with ethyl acetate (2L x 3). The wet cake was dried under vacuum at 40 – 50 °C for 8 hours to give 2.65 – 2.76 kg of (Z)-6-fluoro-3-((l -methyl-lH-l ,2,4-triazol-3- yl)methylene)-4-nitroisobenzofuran-l(3H)-one (3) as a yellow solid (2.66 kg, yield: 75.3 %, purity: 98.6 – 98.8 % by HPLC). LC-MS (ESI) m/z: 291 (M+l)⁺. Ή-ΝΜΡ (400 MHz, DMSO-d₆) δ (ppm): 3.94 (s, 3H), 7.15 (s, 1H), 8.10 (s, 1H), 8.40-8.42 (dd, J_x = 6.4 Hz, J₂ = 2.4 Hz, 1H), 8.58-8.61 (dd, J_x = 8.8 Hz, J₂ = 2.4 Hz, 1H).

Example 2

Methyl 5- enzoate (4)

Example 2A

[0054] (¾-6-Fluoro-3-((l-methyl-lH-l,2,4-taazol-3-yl)m (3) (177 g, 0.6 mol, 1.0 eq.), and HC1 (2 N in methanol, 3 L, 6 mol, 10 eq.) were charged into a 5 L 3-neck flask equipped with mechanical stirrer, thermometer, and nitrogen inlet/outlet. The reaction mixture was stirred at room temperature for 25 hours. The reaction mixture was monitored by HPLC, indicating 0.8 % compound (3) remained. The reaction mixture was concentrated under vacuum at 40 °C to dryness, and methyl 5-fluoro-2-(2-(l -methyl- lH-l,2,4-triazole-3-yl)acetyl)-3-nitrobenzoate hydrochloride (4) was obtained as a yellow solid (201 g, yield: 93.4 %). It was used for the next step without further purification. LC-MS (ESI) m/z: 323 (M+l)⁺ ¾-NMR (400 MHz, DMSO-J₆) δ (ppm): 3.89 (s, 3H), 3.92 (s, 3H), 4.60 (s, 2H), 7.85 (s, 1H), 8.25-8.28 (dd, J_x = 8.4 Hz, J₂ = 2.8 Hz, 2H), 8.52-8.54 (dd, J_x = 8.4 Hz, J₂ = 2.8 Hz, 2H).

Example 2B

An alternative workup procedure to that illustrated in Example 2A follows. Instead of evaporating the reaction mixture to dryness, it was condensed to 2 volumes, followed by solvent exchange with 12 volumes of THF, and then 12 volumes of heptane. The slurry mixture was concentrated to 2 volumes and filtered to give the product. As such, 1.8 kilograms of (Z)-6-fluoro-3-((l-methyl-lH-l,2,4-triazol-3- yl)methylene)-4-nitroisobenzofuran-l(3H)-one (3) gave 2.15 kilograms (yield 96.4 %) of the product methyl 5-fluoro-2-(2-(l -methyl- lH-l,2,4-triazole-3-yl)acetyl)-3-nitrobenzoate hydrochloride (4).

Example 3

Methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4- tetrahydroquinoline-5 -carboxylate (5)

Example 3A

To a suspension of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5-yl)acetyl)-3-nitrobenzoate (4) (5 g, 15.5 mmol, leq.) and 4-fluorobenzaldehyde (3.6 g, 29 mmol, 1.87 eq.) in a mixture of solvents tetrahydrofuran (30 mL) and MeOH (5 mL) was added titanium(III) chloride (20 % w/w solution in 2N Hydrochloric acid) (80 mL, 6 eq.) dropwise with stirring at room temperature. The reaction mixture was allowed to stir at 30~50°C for 2 hours. The mixture was then diluted with water (160 mL), and the resulting solution was extracted with ethyl acetate (100 mL x 4). The combined organic layers were washed with saturated NaHC0₃ (50 mL x 3) and aqueous NaHS0₃ (100 mL x 3), dried by Na₂S0₄, and concentrated to dryness. This afforded a crude solid, which was washed with petroleum ether (120 mL) to obtain the title compound as a yellow solid (5.9 g, yield: 95 %, purity: 97 %). LC-MS (ESI) m/z: 399 (M+l)⁺. ^-NMR (400 MHz, CDCl_a) δ (ppm): 3.58 (s, 3H), 3.87 (s, 3H), 4.16-4.19 (d, J2=13.2 Hz, 1H), 4.88 (s, 1H), 5.37-5.40 (d, J2=13.2 Hz, 1H), 6.47-6.53 (m, 2H) , 6.97-7.01 (m, 2H), 7.37-7.41 (m, 2H), 7.80 (s, 1H).

Example 3B

An alternative workup procedure to that illustrated in Example 3A follows. After the completion of the reaction, the mixture was extracted with isopropyl acetate (20 volumes x 4) without water dilution. The product was isolated by solvent exchange of isopropyl acetate with heptanes followed by re-slurry with MTBE and filtration. As such, 3 kilograms of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5- yl)acetyl)-3-nitrobenzoate (4) afforded 2.822 kilograms of the title compound (5) (yield 81 %).

Example 3C

To a stirred solution of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5-yl)acetyl)-3- nitrobenzoate (4) (580 mg, 2 mmol) and 4-fluorobenzaldehyde (488 mg, 4 mmol) in methanol (0.75 mL) and tetrahydrofuran (4.5 mL) was added concentrated HC1 solution (w/w 37 %, 6 mL), then reductive powdered Fe (672 mg, 12 mmol) was added slowly to the reaction system. After the addition was complete, the resulting mixture was heated to 60 °C and kept at this temperature for 3 hours. After the disappearance of the starting material (4) as monitored by LC-MS, the reaction mixture was partitioned between ethyl acetate (30 mL) and water (30 mL) and the aqueous phase was extracted with ethyl acetate (20 mL x 3). The combined organic phase was dried with Na₂S0₄, concentrated in vacuo and purified by column chromatography (ethyl acetate: petroleum ether = 1 : 1) to give the title compound (5) as a pale yellow solid (300 mg, yield 40 %). LC-MS (ESI) m/z: 399 (M+l)⁺. ^LH-NMR (400 MHz, CDC1₃) δ (ppm): 3.58 (s, 3H), 3.87 (s, 3H), 4.17 (d, 1H), 4.87 (s, 1H), 5.38 (d, 1H), 6.50 (dd, 2H), 6.99 (dd, 2H), 7.38 (dd, 2H), 7.80 (s, 1H).

Example 3D

To a stirred solution of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5-yl)acetyl)-3- nitrobenzoate (4) (580 mg, 2 mmol) and 4-fluorobenzaldehyde (488 mg, 4 mmol) in methanol (0.75 mL) and tetrahydrofuran (4.5 mL) was added SnCl₂ (2.28 g, 12 mmol) and concentrated HC1 (w/w 37 %, 6 mL), the resulting mixture was reacted at 45 °C for 3 hours, until LC-MS indicating the disappearance of the starting material (4) and about 50 % formation of the product. The mixture was then partitioned between ethyl acetate (30 mL) and water (30 mL) and the aqueous phase was extracted with ethyl acetate (20 mL x 3). The combined organic phase was dried with Na₂S0₄, concentrated in vacuo and purified by column chromatography (ethyl acetate: petroleum ether = 1 : 1) to give the title compound (5) as a pale yellow solid (10 mg, yield 1.3 %). LC-MS (ESI) m/z: 399 (M+l)⁺. ^LH-NMR (400 MHz, CDC1₃) δ (ppm): 3.58 (s, 3H), 3.87 (s, 3H), 4.17 (d, 1H), 4.87 (s, 1H), 5.38 (d, 1H), 6.50 (dd, 2H), 6.99 (dd, 2H), 7.38 (dd, 2H), 7.80 (s, 1H).

Example 3E

A solution of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5-yl)acetyl)-3-nitrobenzoate (4) (580 mg, 2 mmol) and 4-fluorobenzaldehyde (488 mg, 4 mmol) in methanol (20 mL) and acetic acid (1 mL) was stirred at room temperature for 24 hours under hydrogen (1 barr) in the presence of a catalytic amount of 10 % Pd/C (212 mg, 0.2 mmol). After the reaction was complete, the catalyst was removed by filtration through a pad of Celite, the solvent was removed in vacuo, and the residue was purified by column chromatography (ethyl acetate: petroleum ether = 1 : 1) to give the title compound (5) as a pale yellow solid (63 mg, yield 8 %). LC-MS (ESI) m/z: 399 (M+l)⁺ . ¹HNMR (400 MHz, DMSO-d₆) δ (ppm): 3.56 (s, 3H), 3.86 (s, 3H), 7.02 (dd, 2H), 7.21 (dd, 2H), 7.90 (s, 1H), 8.08 (s, 1H), 8.26 (dd, 1H), 8.56 (dd, 1H).

Example 4

5-Fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-

Methyl 7-fluoro-2-(4-fluorophenyl)-3-(l -methyl-lH-l ,2,4-triazol-5-yl)-4-oxo-l,2,3,4- tetrahydroquinoline-5-carboxylate (5) (150 g, 0.38 mol, 1.0 eq.) and methanol (1.7 L) were charged into a 3 L 3-neck flask equipped with a mechanical stirrer, thermometer, and nitrogen inlet/outlet. The resulted suspension was stirred at room temperature for 15 minutes. Hydrazine hydrate (85 % of purity, 78.1 g, 1.33 mol, 3.5 eq.) was charged dropwise into the above reaction mixture within 30 minutes at ambient temperature. The reaction mixture was stirred at room temperature overnight. The reaction was monitored by HPLC, showing about 2 % of compound (5) left. The obtained slurry was filtered. The wet cake was suspended in methanol (2 L) and stirred at room temperature for 3 hours. The above slurry was filtered, and the wet cake was washed with methanol (0.5 L). The wet cake was then dried in vacuum at 45 – 55 °C for 12 hours. This afforded the title compound as a pale yellow solid (112 g, yield: 78.1 %, purity: 95.98 % by HPLC). LC-MS (ESI) m/z: 381 (M+l)⁺. ^-NMR (400 MHz, DMSO-J₆) δ (ppm): 3.66 (s, 3H), 4.97-5.04 (m, 2H), 6.91-6.94 (dd, J_x = 2.4, J₂ = 11.2 Hz, 1H), 7.06-7.09 (dd, J_x = 2.4, J₂ = 8.8 Hz, 1H), 7.14-7.18 (m, 3H), 7.47-7.51 (m, 2H), 7.72 (s, 1H), 7.80 (s, 1H), 12.35 (s, 1H).

Example 5

5 -Amino-7-flu in- 1 (2H)-one

To a solution of 6-fluoro-3-((l-methyl-lH-l,2,4-triazol-3-yl)methylene)-4-nitroiso-benzofuran- l(3H)-one (3) (4.0 g, 135 mmol) in THF (100 mL) was added hydrazine monohydrate (85 %) (6 mL) at room temperature under nitrogen atmosphere. The mixture was stirred for 2 hours, then acetic acid (6 mL) was added and the mixture was heated to and kept at 60 °C for 18 hours. The resulting mixture was diluted with water (100 mL) and extracted with ethyl acetate (100 mL x 3). The organic layer was dried over anhydrous Na₂S0₄ and evaporated to dryness to afford the title compound as a yellow solid (1.6 g, yield 42 %). LC-MS (ESI) m/z: 275(M+1)⁺.

Example 6

(£’)-7-fluoro-5-(4-fluorobenzylideneamino)-4-((l -methyl- IH- 1 ,2,4-triazol-5-yl)methyl)phthalazin- 1 (2H)- one

(7)

To a suspended of 5-amino-7-fluoro-4-((l-methyl-lH-l,2,4-triazol-3-yl)methyl) phthalazin- l(2H)-one (7) (1.6 g, 5.8 mmol) in acetonitrile (50 mL) was added 4-fluorobenzaldehyde (2.2 g, 17.5 mmol). The mixture was stirred under reflux under nitrogen for 48 hours. The precipitate was filtered and washed with a mixture of solvents (ethyl acetate/hexane, 1 :1, 10 mL). After drying in vacuum, it afforded the title compound as a yellow solid (1.2 g, yield 52 %). LC-MS (ESI) m/z: 381(M+1)⁺.

Example 7

5-Fluoro-8 4-fluorophenyl)-9 l-methyl H-l,2,4-triazol-5-yl)-8,9-dihydro-2H^yrido[4,3,2-

(8) (1 )

To a suspension of (£’)-7-fluoro-5-(4-fluorobenzylideneamino)-4-((l-methyl-lH-l,2,4-triazol-5- yl)methyl)phthalazin-l(2H)-one (8) (2.0 g, 5.3 mmol) in THF (80 mL) was added cesium carbonate (3.4 g, 10.6 mmol). The reaction mixture was stirred at 55 °C for 4 hours and cooled down to room temperature. The mixture was diluted with water (50 ml) and extracted with ethyl acetate (50 mL x 3). The combined organic layers were dried over anhydrous Na₂S0₄ and evaporated to dryness to afford the title compound as a white solid (1.6 g, yield 80 %). LC-MS (ESI) m/z: 381(M+1)⁺. ^-NMR (400 MHz, DMSO- ) δ (ppm): 3.66 (s, 3H), 4.97-5.04 (m, 2H), 6.91-6.94 (dd, J_x = 2.4, J₂ = 11.2 Hz, 1H), 7.06-7.09 (dd, Ji = 2.4, J₂ = 8.8 Hz, 1H), 7.14-7.18 (m, 3H), 7.47-7.51 (m, 2H), 7.72 (s, 1H), 7.80 (s, 1H), 12.35 (s, 1H).

Example 8

(£)-Methyl 5-fluoro-2-(3-(4-fluorophenyl)-2-(l-methyl-lH-l,2,4-triazol-5-yl)acryloyl)-3-nitrobenzoate

(9)

To a stirred solution of methyl 5-fluoro-2-(2-(l-methyl-lH-l,2,4-triazol-5-yl)acetyl)-3- nitrobenzoate (4) (580mg, 2 mmol) and 4-fluorobenzaldehyde (488 mg, 4 mmol) in dimethylsulfoxide (2 mL) was added L-proline (230 mg, 2 mmol). The resulting mixture was kept with stirring at 45 °C for 48 hours. The reaction system was then partitioned between ethyl acetate (50 mL) and water (30 mL), and the organic phase was washed with water (20 mL x 3), dried with Na₂S0₄, concentrated in vacuo, and purified by column chromatography (ethyl acetate: petroleum ether = 1 :3) to give the title compound (9) as a pale yellow foam (340 mg, yield 40 %). LC-MS (ESI) m/z: 429 (M+l)⁺. ^-NMR (400 MHz, DMSO-dg); δ (ppm): 3.56 (s, 3H), 3.86 (s, 3H), 7.02 (dd, 2H), 7.21 (dd, 2H), 7.90 (s, IH), 8.08 (s, IH), 8.26 (dd, IH), 8.56 (dd, IH).

Example 9

Methyl 7-fluoro-2-(4-fluorophenyl)- 1 -hydroxy-3-( 1 -methyl- IH- 1 ,2,4-triazol-5-yl)-4-oxo- 1 ,2,3,4- tetrahydroquinoline-5 -carboxylate (10)

To a solution of (£)-Methyl 5-fluoro-2-(3-(4-fluorophenyl)-2-(l-methyl-lH-l,2,4-triazol-5- yl)acryloyl)-3-nitrobenzoate (9) (200 mg, 0.467 mmol) in methanol (20 mL) was added 10 % Pd/C (24 mg). After the addition, the mixture was stirred under H₂ (1 atm) at room temperature for 0.5 h. The reaction system was then filtered and evaporated under reduced pressure. The residue was purified by chromatography (ethyl acetate: petroleum ether = 1 :1) to give the title compound (10) (110 mg, yield 57 %) as an off-white foam. LC-MS (ESI) m/z: 415 (M+H)⁺. ¾-NMR (400 MHz, DMSO-d₆) δ (ppm): 3.53 (s, 3H), 3.73 (s, 3H), 5.08 (d, 2H), 5.27 (d, 2H), 6.95 (dd, IH), 7.08 (dd, 2H), 7.15 (dd, IH), 7.42 (dd, 2H), 7.77 (s, IH), 9.92 (s, IH). Example 10

Methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4-

(10) (5)

To a stirred solution of methyl 7-fluoro-2-(4-fluorophenyl)-l-hydroxy-3-(l-methyl-lH-l,2,4- triazol-5-yl)-4-oxo-l, 2,3, 4-tetrahydroquinoline-5 -carboxylate (10) (41.4 mg, 0.1 mmol) in methanol (5 mL) was added concentrated HCl solution (w/w 37 %, 1 mL) and reductive powdered Fe (56 mg, 1 mmol). The reaction mixture was refluxed for 3 hours. After the disappearance of compound (10) as monitored by LC-MS, the reaction system was partitioned between ethyl acetate (20 mL) and water (20 mL) and then the aqueous phase was extracted with ethyl acetate (10 mL x 3). The combined organic phase was dried with Na₂S0₄, concentrated in vacuo and purified by column chromatography (ethyl acetate: petroleum ether = 1 :1) to give the title compound (5) as a pale yellow solid (12 mg, yield 30 %). LC-MS (ESI) m/z: 399 (M+l)⁺. ¾-NMR (400 MHz, CDC1₃) δ (ppm): 3.58 (s, 3H), 3.87 (s, 3H), 4.17 (d, 1H), 4.87 (s, 1H), 5.38 (d, 1H), 6.50 (dd, 2H), 6.99 (dd, 2H), 7.38 (dd, 2H), 7.80 (s, 1H).

Example 11

Methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4-

To a solution of (£)-Methyl 5-fluoro-2-(3-(4-fluorophenyl)-2-(l-methyl-lH-l,2,4-triazol-5- yl)acryloyl)-3-nitrobenzoate (9) (214 mg, 0.5 mmol) in methanol (5 mL) was added concentrated HCl solution (w/w 37 %, 1 mL), then reductive Fe powder (140 mg, 2.5 mmol) was added slowly to the reaction system. After the addition was complete the resulting mixture was refluxed for 24 hours. The reaction mixture was then filtered, concentrated, neutralized with saturated NaHC0₃ (20 mL), and extracted with ethyl acetate (10 mL x 3). The residue was purified by chromatography (ethyl acetate: petroleum ether = 1 : 1) to give the title compound (5) (30 mg, yield 15 %) as an off-white foam. LC-MS (ESI) m/z: 399 (M+H)⁺. ^-NMR (400 MHz, DMSO-d₆) δ (ppm): 3.56 (s, 3H), 3.86 (s, 3H), 7.02 (dd, 2H), 7.21 (dd, 2H), 7.90 (s, 1H), 8.08 (s, 1H), 8.26 (dd, 1H), 8.56 (dd, 1H).

Example 12

(8R,9S)-5-fluoro-8-(4-fluorophenyl)-9-(l-me

Je]phthalazin-3(7H)-one (la) and (8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-

(1) (la) (lb)

A chiral resolution of 5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5-yl)-8,9- dihydro-2H-pyrido[4,3,2-Je]phthalazin-3(7H)-one (1) (52.5 g) was carried out on a super-fluid chromatography (SFC) unit using a CHIRALPAK IA column and C0₂/methanol/diethylamine

(80/30/0.1) as a mobile phase. This afforded two enantiomers with retention times of 7.9 minute (23.6 g, recovery 90 %, > 98 % ee) and 9.5 minute (20.4 g, recovery 78 %, > 98 % ee) as analyzed with a CHIRALPAK IA 0.46 cm x 15 cm column and C0₂/methanol/diethylamine (80/30/0.1) as a mobile phase at a flow rate of 2 g/minute.

Example 13

(2R,3R)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4- tetrahydroquinoline-5-carboxylate (6a) and (2S,3S)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-

(5) (6a) (6b)

Example 13A

The chiral resolution of compound (5) was carried out on a SFC unit with a CHIRALPAK®IC 3 cm (I.D.) x 25 cm, 5 μηι column, using C0₂/MeOH (80/20) as a mobile phase at a flow rate of 65 g/ minute while maintaining the column temperature at 35 °C and with a detection UV wavelength of 254 nm. As such, a racemate of compound (5) (5 g) in methanol solution was resolved, which resulted in two enantiomers with a retention times of 2.35 minute (2.2 g, 88 % recovery, >98 % ee) and 4.25 minute (2.3 g, 92 % recovery, >98 % ee), respectively when analyzed using CHIRALPAK®IC 0.46 cm x 15 cm column and CO₂/MeOH(80/20) as a mobile phase at a flow rate of 2 mL/ minute.

Example 13B

The chiral resolution of compound (5) was carried out on a SFC unit with a CHIRALPAK®IC 5cm (I.D.) x 25 cm, 5 μηι column, using C0₂/MeOH (75/25) as a mobile phase at a flow rate of 200 mL/ minute while maintaining the column temperature at 40 °C and with a detection UV wavelength of 255 nm. As such, a racemate of compound (5) (1.25 kg) in methanol solution was resolved, which resulted in two enantiomers in about 83 % yield and 97.4 % purity.

Example 13C

Alternatively, the separation can also be achieved on a Simulated Moving Bed (SMB) unit with a CHIRALPAK®IC column and acetonitrile as a mobile phase. The retention times for the two enantiomers are 3.3 and 4.1 minutes, respectively. In certain embodiments, the productivity can be greater than 6 kg Feed/day/kg CSP.

Example 14

(8R,9S)-5-fluoro-8 4-fluorophenyl)-9<l-me

Je]phthalazin-3(7H)-one (la) and (8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(l-methyl-lH-l,2,4-triazol-5- (lb)

Example 14A

To a solution of (2R,3R)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)- 4-oxo-l,2,3,4-tetrahydroquinoline-5-carboxylate (6a) or (2S,3S)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l- methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4-tetrahydroquinoline-5-carboxylate (6b) (400 mg, 1.0 mmol) in ethanol (8.0 mL) was added hydrazine monohydrate (85 %, 2.0 mL), and the solution stirred at room temperature for 2 hours. The resulting solution was then concentrated to a volume of 2 mL and filtered, and the resultant cake washed with ethanol (1 mL). After drying in vacuum at 50°C, this afforded the title compound as a white solid (209 mg, yield 55 %). LC-MS (ESI) m/z: 381(M+1)⁺. ^-NMR (400 MHz, DMSO-dg): δ (ppm): 3.681 (s, 3H), 4.99-5.06 (m, 2H), 6.92-6.96 (m, 1H), 7.08-7.11 (m, 1H), 7.16-7.21 (t, J= 8.8 Hz, 2H), 7.49-7.53 (m, 2H), 7.75 (s, 1H), 7.83 (s, 1H), 12.35 (s, 1H).

Example 14B

To a solution of (2R,3R)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l-methyl-lH-l,2,4-triazol-5-yl)- 4-oxo-l,2,3,4-tetrahydroquinoline-5-carboxylate (6a) or (2S,3S)-methyl 7-fluoro-2-(4-fluorophenyl)-3-(l- methyl-lH-l,2,4-triazol-5-yl)-4-oxo-l,2,3,4-tetrahydroquinoline-5-carboxylate (6b) (446 g) in acetonitrile (10 volume) was added hydrazine monohydrate (2.9 eq.), and the solution stirred at room temperature for 2 hours. The resulting solution was then concentrated to a volume of 2 mL and filtered. The crude product was re-slurried with water (3~5 volumes) at 15-16 °C. After drying in vacuum at 50 °C, this affords the title compound as a white solid (329 g, yield 77%, 99.93% purity). LC-MS (ESI) m/z:

381(M+1)⁺; ¾-NMR (400 MHz, DMSO-d₆) δ (ppm): 3.681 (s, 3H), 4.99-5.06 (m, 2H), 6.92-6.96 (m, 1H), 7.08-7.11 (m, 1H), 7.16-7.21 (t, J= 8.8 Hz, 2H), 7.49-7.53 (m, 2H), 7.75 (s, 1H), 7.83 (s, 1H), 12.35 (s, 1H).

Talazoparib (BMN-673) is an orally available poly ADP ribose polymerase (PARP) inhibitor currently in development by Pfizer for the treatment of advanced breast cancer patients with germline BRCA mutations.^[1] Talazoparib is similar to the first in class PARP inhibitor, olaparib.^[2]^[3] However, talazoparib is thought to be more potent than olaparib.^[3]

Mechanism of action

Talazoparib acts as an inhibitor of poly ADP ribose polymerase(PARP) which aids in single strand DNA repair. Cells that have BRCA1/2mutations are susceptible to the cytotoxic effects of PARP inhibitors because of an accumulation of DNA damage.^[1] Talazoparib is theorized to have a higher potency than olaparib due to the additional mechanism of action called PARP trapping. PARP trapping is the mechanism of action where the PARP molecule is trapped on the DNA, which interferes with the cells ability to replicate. Talazoparib is found to be ~100 fold more efficient in PARP trapping than olaparib.^[4] However, this increased potency may not translate directly to clinical effectiveness as many other factors must be considered.^[3]^[4]

Commercialization

Talazoparib was originally developed by BioMarin Pharmaceutical Inc. However, Medivation Inc. acquired all worldwide rights to talazoparib in August 2015 to expand their global oncology franchise.^[5] Medivation acquired talazoparib for $410 million with additional payments of up to $160 million in royalties and milestones. Under this agreement, Medivation assumed all financial responsibilities for the continued development, regulatory, and commercialization of talazoparib.^[5]^[6]

Clinical trials

As of January 2016, talazoparib is in 14 active clinical trials ^[7] including a new arm of I-SPY 2.^[8] These trials cover a variety of cancers types and combination therapies. The most notable clinical trials are the ABRAZO and EMBRACA studies.

ABRAZO

ABRAZO is a phase II study for the safety and efficacy of treatment of BRCA breast cancer patients with Talazoparib monotherapy. This study is for patients who have failed at least two prior chemotherapy treatments for metastatic breast cancer or been previously treated with a platinum regimen.^[6]^[9]^[10] The original target enrollment for the study was 70 patients but Biomarin expanded the trial to 140 patients.^[9]^[10] The estimated completion date is December 2016.^[10]

EMBRACA

EMBRACA is a phase III study for the treatment of BRCA breast cancer patients with Talazoparib.^[11]^[12]^[13] This trial is an open-label, randomized, parallel, 2-arm, multi-center comparison of talazaporib against physician’s preference for the treatment of patients with locally advanced or metastatic breast cancer. Patients must also have received prior chemotherapy regimens for metastatic breast cancer.^[12]^[13] Patients participating in this study are randomly selected for either talazoparib or physician’s choice of chemotherapy at a 2:1 ratio to talazoparib.^[6] The target enrollment for the study was 430 patients ^[12]^[13] and the estimated completion date is June 2017.^[13]

References

^ Jump up to:^a ^b Medivation Inc. “Talazoparib”.
Jump up^ FDA (19 December 2014). “FDA approves Lynparza to treat advanced ovarian cancer”. FDA News Release.
^ Jump up to:^a ^b ^c Jessica Brown, Stan Kaye, Timothy Yap (29 March 2016). “PARP inhibitors: the race is on”. British Journal of Cancer. 114: 713–5. doi:10.1038/bjc.2016.67. PMC 4984871 . PMID 27022824.
^ Jump up to:^a ^b Yuqiao Shen, Mika Aoyagi-Scharber, Bing Wang (June 2015). “Trapping Poly(ADP-Ribose) Polymerase”. Journal of Pharmacology and Experimental Therapeutics.
^ Jump up to:^a ^b Biomarin (24 August 2015). “Medivation to Expand Global Oncology Franchise With the Acquisition of All Worldwide Rights to Talazoparib (BMN 673), a Potent PARP Inhibitor, From BioMarin”.
^ Jump up to:^a ^b ^c Silus Inman (25 August 2015). “Medivation Acquires BioMarin’s PARP Inhibitor Talazoparib”.
Jump up^ BMN 673 trials registered
Jump up^ I-SPY 2 TRIAL: Neoadjuvant and Personalized Adaptive Novel Agents to Treat Breast Cancer (I-SPY 2)
^ Jump up to:^a ^b “BioMarin Provides Program Update for Talazoparib in Metastatic Breast Cancer”. 20 July 2015.
^ Jump up to:^a ^b ^c “A Phase 2, 2-Stage, 2-Cohort Study of Talazoparib (BMN 673), in Locally Advanced and/or Metastatic Breast Cancer Patients With BRCA Mutation (ABRAZO Study)”. ClinicalTrials.gov.
Jump up^ “EMBRACA CLINICAL STUDY IS NOW ENROLLING”.
^ Jump up to:^a ^b ^c “A Study Evaluating Talazoparib (BMN 673), a PARP Inhibitor, in Advanced and/or Metastatic Breast Cancer Patients With BRCA Mutation (EMBRACA Study)”. ClinicalTrials.gov.
^ Jump up to:^a ^b ^c ^d “BioMarin Initiates Phase 3 BMN 673 Trial for Metastatic gBRCA Breast Cancer”. Benzinga.

External links

Talazoparib. Chemspider.com structure etc

nmr……http://www.medkoo.com/uploads/product/Talazoparib__BMN-673_/qc/BMN673-QC-BBC20130523-Web.pdf

Patent Submitted Granted

PROCESSES OF SYNTHESIZING DIHYDROPYRIDOPHTHALAZINONE DERIVATIVES [US2014323725]2014-06-022014-10-30

CRYSTALLINE (8S,9R)-5-FLUORO-8-(4-FLUOROPHENYL)-9-(1-METHYL-1H-1,2,4-TRIAZOL-5-YL)-8,9-DIHYDRO-2H-PYRIDO[4,3,2-DE]PHTHALAZIN-3(7H)-ONE TOSYLATE SALT [US2014228369]2014-04-142014-08-14

Crystalline (8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-de]phthalazin-3(7H)-one tosylate salt [US8735392]2011-10-202014-05-27

DIHYDROPYRIDOPHTHALAZINONE INHIBITORS OF POLY(ADP-RIBOSE)POLYMERASE (PARP) [US8012976]2010-02-112011-09-06

DIHYDROPYRIDOPHTHALAZINONE INHIBITORS OF POLY(ADP-RIBOSE)POLYMERASE (PARP) FOR USE IN TREATMENT OF DISEASES ASSOCIATED WITH A PTEN DEFICIENCY [US2014066429]2013-08-212014-03-06

METHODS AND COMPOSITIONS FOR TREATMENT OF CANCER AND AUTOIMMUNE DISEASE [US2013184342]2013-03-132013-07-18

WO2012054698A1	Oct 20, 2011	Apr 26, 2012	Biomarin Pharmaceutical Inc.	Crystalline (8s,9r)-5-fluoro-8-(4-fluorophenyl)-9-(1-methyl-1h-1,2,4-triazol-5-yl)-8,9-dihydro-2h-pyrido[4,3,2-de]phthalazin-3(7h)-one tosylate salt
WO2015069851A1	Nov 6, 2014	May 14, 2015	Biomarin Pharmaceutical Inc.	Triazole intermediates useful in the synthesis of protected n-alkyltriazolecarbaldehydes
US8420650	Mar 31, 2011	Apr 16, 2013	Biomarin Pharmaceutical Inc.	Dihydropyridophthalazinone inhibitors of poly(ADP-ribose)polymerase (PARP)
US8541403	Feb 3, 2011	Sep 24, 2013	Biomarin Pharmaceutical Inc.	Dihydropyridophthalazinone inhibitors of poly(ADP-ribose)polymerase (PARP) for use in treatment of diseases associated with a PTEN deficiency
US8735392	Oct 20, 2011	May 27, 2014	Biomarin Pharmaceutical Inc.	Crystalline (8S,9R)-5-fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-8,9-dihydro-2H-pyrido[4,3,2-de]phthalazin-3(7H)-one tosylate salt
US8765945	Feb 8, 2011	Jul 1, 2014	Biomarin Pharmaceutical Inc.	Processes of synthesizing dihydropyridophthalazinone derivatives
US8999987	Mar 6, 2013	Apr 7, 2015	Biomarin Pharmaceutical Inc.	Dihydropyridophthalazinone inhibitors of poly(ADP-ribose)polymerase (PARP)
US9018201	Aug 21, 2013	Apr 28, 2015	Biomarin Pharmaceuticial Inc.	Dihydropyridophthalazinone inhibitors of poly(ADP-ribose)polymerase (PARP) for use in treatment of diseases associated with a PTEN deficiency

SEE………..http://orgspectroscopyint.blogspot.in/2016/02/talazoparib.html

http://apisynthesisint.blogspot.in/2016/02/talazoparib.html

Talazoparib
Systematic (IUPAC) name

(8S,9R)-5-Fluoro-8-(4-fluorophenyl)-9-(1-methyl-1H-1,2,4-triazol-5-yl)-2,7,8,9-tetrahydro-3H-pyrido[4,3,2-de]phthalazin-3-one
Clinical data
Legal status	Investigational
Chemical data
Formula	C₁₉H₁₄F₂N₆O
Molar mass	380.35 g/mol

Talazoparib
Legal status

Legal status	Investigational
Identifiers
IUPAC name [show]
ChemSpider	28637772
UNII	9QHX048FRV
KEGG	D10732
ChEMBL	CHEMBL3137320
Chemical and physical data
Formula	C₁₉H₁₄F₂N₆O
Molar mass	380.35 g/mol
3D model (JSmol)	Interactive image

/////////////BMN 673, talazoparib, phase 3, BMN673, BMN673, BMN-673, LT673, LT 673, LT-673, Poly ADP ribose polymerase 2 inhibitor, Poly ADP ribose polymerase 1 inhibitor, cancer, MDV-3800 , MDV 3800

Cn1c(ncn1)[C@H]2c3c4c(cc(cc4N[C@@H]2c5ccc(cc5)F)F)c(=O)[nH]n3

O=C1NN=C2C3=C1C=C(F)C=C3N[C@H](C4=CC=C(F)C=C4)[C@H]2C5=NC=NN5C

New Website ECA Validation Group: Version 02 of ECA´s Good Practice Guide on Validation online available

February 4, 2016 3:26 am / Leave a comment

The ECA Validation Group was founded in autumn 2011 by representatives of the pharmaceutical industry after ECA´s 4th European GMP Conference. The mission of the group is to assemble knowledge on Validation, for example by continuously developing ECA´s Process Validation Good Practice Guide. Now the Validation Group launched a new website.

Since the ECA Foundation was established back in 1999 its mission has been to provide support to the Pharmaceutical Industry and Regulators to promote the move towards a harmonised set of GMP and regulatory guidelines by providing information and interpretation of new or updated guidances. For that purpose the ECA has initiated and established various working and interest groups concentrating on different topics.

The ECA Validation Group was founded in autumn 2011 by representatives of the pharmaceutical industry after ECA´s 4th European GMP Conference. This group’s mission is to assemble knowledge on Validation, for example by continuously developing ECA´s Process Validation Good Practice Guide.

Now the group launched its new website to provide members and those interested with information and practical tools. Here’s what you can find on the new website:

Current News
A news archive
Training Courses and Validation Conferences
ECA´s Process Validation Good Practice Guide
Discussion Forum
Presentations
Useful links
Q&A section
Membership information

Members of the group have now the opportunity to download the version 2 of ECA´s Good Practice Guide on Validation free of charge. On 174 pages the revised Good Practice Guide comprises the main elements of the new validation approach (“what to do”). On the other hand, it also serves as a supporting guide for the implementation (“how to do”).

To find out more we invite you to visit the ECA´s Validation Group new website.

//////

PF 04995274, a 5-HT4Partial Agonist

February 3, 2016 5:19 am / Leave a comment

PF-04995274,

(R)-4-((4-(((4-(Tetrahydrofuran-3-yloxy)-1,2-benzisoxazol-3-yl)oxy)methyl)piperidin-1-yl)methyl)tetrahydro-2H-pyran-4-ol

4-(4-{4-[(R)-(Tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-yloxymethyl}-piperidin-1-ylmethyl)-tetrahydro-pyran-4-ol

CAS 1331782-27-4
UNII: XI179PG9LV

MF C23-H32-N2-O6

MW 432.5138

a 5-HT4Partial Agonist

PHASE 1 Alzheimer’s type dementia.

Pfizer Inc. INNOVATOR

5-HT₄ agonists have attracted attention for therapeutic value in the treatment of Alzheimer’s Disease (AD) and cognitive impairment.Acting to increase levels of acetylcholine and soluble APP alpha, 5-HT₄ agonists have the potential to demonstrate both ameliorative and disease modifying effects

(R)-4-((4-((4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazol-3-yloxy)methyl)piperidin-1-yl)methyl)tetrahydro-2/-/-pyran-4-ol and pharmaceutically acceptable salts thereof. This invention also is directed, in part, to a method for treating a 5-HT₄ mediated disorder in a mammal. Such disorders include acute neurological and psychiatric disorders, stroke, cerebral ischemia, spinal cord trauma, head trauma, perinatal hypoxia, cardiac arrest, hypoglycemic neuronal damage, dementia, Alzheimer’s disease, Huntington’s Chorea, amyotrophic lateral sclerosis, ocular damage, retinopathy, cognitive disorders, idiopathic and drug- induced Parkinson’s disease, muscular spasms and disorders associated with muscular spasticity including tremors, depression, epilepsy, convulsions, migraine, urinary incontinence, substance tolerance, substance withdrawal, psychosis, schizophrenia, anxiety, mood disorders, trigeminal neuralgia, hearing loss, tinnitus, macular degeneration of the eye, gastroesophageal reflux disease, gastrointestinal disease, gastric motility disorder, non-ulcer dyspepsia, functional dyspepsia, irritable bowel syndrome, constipation, dyspepsia, esophagitis, gastroesophageral disease, nausea, emesis, brain edema, pain, tardive dyskinesia, sleep disorders, attention deficit/hyperactivity disorder, attention deficit disorder, disorders that comprise as a symptom a deficiency in attention and/or cognition, and conduct disorder

^a(a) SOCl₂, DMAP, acetone, DME, RT, 81%;

(b) DEAD, PPh₃, THF, RT, 65%;

(d) K₂CO₃, water, MeOH, 50 °C, 76%;

(e) CDI, THF, 50 °C, 43%;

(f) DEAD, PPh₃, THF, reflux, 51%;

(g) HCl, Et₂O, RT, 81%;

(h) TEA, MeOH, reflux, 50%.

PAPER

Journal of Medicinal Chemistry (2012), 55(21), 9240-9254

http://pubs.acs.org/doi/abs/10.1021/jm300953p

The cognitive impairments observed in Alzheimer’s disease (AD) are in part a consequence of reduced acetylcholine (ACh) levels resulting from a loss of cholinergic neurons. Preclinically, serotonin 4 receptor (5-HT₄) agonists are reported to modulate cholinergic function and therefore may provide a new mechanistic approach for treating cognitive deficits associated with AD. Herein we communicate the design and synthesis of potent, selective, and brain penetrant 5-HT₄ agonists. The overall goal of the medicinal chemistry strategy was identification of structurally diverse clinical candidates with varying intrinsic activities. The exposure–response relationships between binding affinity, intrinsic activity, receptor occupancy, drug exposure, and pharmacodynamic activity in relevant preclinical models of AD were utilized as key selection criteria for advancing compounds. On the basis of their excellent balance of pharmacokinetic attributes and safety, two lead 5-HT₄ partial agonist candidates 2d and 3 were chosen for clinical development.

PATENT

https://www.google.co.in/patents/WO2011101774A1?cl=en

(R)-4-((4-((4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazol-3-yloxy)methyl)piperidin-1-yl)methyl)tetrahydro-2H-pyran-4-ol , hereinafter referred to as “Compound X,” and having the following structure:

Compound X

Example 1 : Synthesis of iR)-4-ii4-i(4-itetrahvdrofuran-3-yloxy)benzord1isoxazol-3-yloxy)methyl)piperidin-1 -yl)methyl)tetrahvdro- 2 -pyran-4-ol

Methyl 2-fluoro-6-hydroxybenzoate (2): To a 20L jacketed reactor were charged 2-fluoro-6-hydroxybenzoic acid (Oakwood Products; 0.972 kg, 6.31 mol), methanol (7.60 L) and sulfuric acid (0.710 kg, 7.24 mol, 1 .15 eq). The jacket temperature was heated to 60°C and the reaction mixture was stirred for 45 h. The reaction mixture was concentrated under vacuum and approximately 7.5 L of methanol distillates were collected. The resulting thin oil was cooled to 20°C. Water (7.60 L) and ethyl acetate (7.60 L) were charged to the reactor, and the product extracted into the organic layer. The EtOAc solution was washed with a solution of sodium bicarbonate (1.52 Kg) in water (6.92 L) followed by a brine solution of sodium chloride (1.74 kg) in water (4.08 L). The resulting EtOAc solution was concentrated to dryness. A light orange oil was isolated; the oil slowly crystallized upon standing to give the title compound (2) (0.952 Kg, 5.60 mol, 89% yield). ¹ H NMR (400 MHz, CDCI₃) δ ppm 3.97 (s, 3H), 6.59 (ddd, J=10.9, 8.2,1 .2, 1 H), 6.76 (dt, J=8.2, 1 .1 , 1 H), 7.35 (td, J=8.6, 6.3, 1 H), 1 1.24 (s, 1 H); ¹³C NMR (400 MHz, CDCI₃) δ ppm 52.65, 102.56 (d, J=13), 106.90 (d, J=23), 1 13.31 (d, J=3.1 ), 135.34 (d, J=1 1 .5), 161 .02, 163.31 (d, J=62.2), 169.87 (d, 3.8); MS 171.045 (m+1 ). 2-Fluoro-N,6-dihydroxybenzamide (3): To a 50L reactor was charged water (4.47 L) and hydroxylamine sulfate (6.430 kg, 39.17 mol), the mixture was stirred at 25°C. A solution of potassium carbonate (3.87 Kg, 27.98 mol) in water (5.05 L) was slowly added to the reaction mixture to form a thick white mixture that was stirred at 20°C. A solution of methyl 2-fluoro-6-hydroxybenzoate (2) (0.952 Kg, 5.60 mol) in methanol (9.52 L) was slowly added to the reactor resulting in mild off gassing. The reaction mixture was then heated to 35°C and stirred for 20 h. The reaction mixture was cooled to 15°C and stirred for 1 h. The mixture was filtered to remove inorganic material. The reactor was rinsed with methanol (2.86 L) and the tank rinse was used to wash the inorganic cake.

Analysis of the cake indicated that it contained product. To a 20L reactor was charged methanol (10 L) and the inorganic cake and the mixture was stirred at 25°C for 30 min. The mixture was filtered and the cake washed with methanol (3 L).

The combined filtrates were charged back into the reactor and concentrated under vacuum with the jacket temperature set at 40°C until approximately 10 L remained. The mixture was held at 25°C and cone. HCI (5.51 L) was added. The reactor was cooled to 15°C and stirred for 2 h. The white slurry was filtered and the resulting product cake was washed with water (4.76L), blown dry with nitrogen and then dried in a vacuum oven at 40°C for 12 h. The desired product (3) (747 g, 4.36 mol), was isolated in 78% yield. ¹ H NMR (400 MHz, CD₃OD) δ ppm 4.91 (s, 3H), 6.63 (ddd, J=10.9, 8.5, 0.8, 1 H), 6.72 (dt, J=8.2, 0.8, 1 H), 7.31 (td, J=8.2, 6.6, 1 H); MS 172.040 (m+1 ).

4-Fluorobenzo[d]isoxazol-3-ol (4): To a 20L jacketed reactor were charged tetrahydrofuran (2.23 L) and 1 ,1 ‘-carbonyldiimidazole (0.910 Kg, 5.64 mol). The resulting mixture was stirred at 20°C. Then a solution of 2-fluoro-N,6-dihydroxybenzamide (3) (744 g, 4.34 mol) in tetrahydrofuran (4.45 L) was slowly charged to the reactor maintaining the temperature below 30°C and stirred at 25°C for 30 min during which some off gassing was observed. The reaction mixture was heated to 60°C over 30 min and stirred for 6 h. The reactor was cooled to 20°C followed by the addition of 1 N aqueous hydrogen chloride (7.48L) over 15 min to adjust the pH to 1. The jacket temperature was set to 35°C and the reaction mixture concentrated under vacuum to remove approximately 6.68L of THF. The reactor was cooled to 15°C and stirred for 1 h. The resulting white slurry was filtered, the cake was washed with water (3.71 L) and dried in a vacuum oven at 40°C for 12 h. The desired product, (4) (597 g, 3.90 mol), was isolated in 90% yield. ¹ H NMR (400 MHz, CD₃OD) δ ppm 4.93 (b, 1 H), 6.95 (dd, J=10.1 , 8.6, 1 H), (d, J=8.6, 1 H), 7.52-7.57 (m, 1 H); LRMS 154.029 (m+1 ).

Tert-butyl 4-(tosyloxymethyl)piperidine-1-carboxylate (5): To a 20L jacketed reactor were charged dichloromethane (8 L), N-boc-4-piperdine methanol (0.982 Kg, 4.56 mol) and p-toluenesulfonyl chloride (0.970 Kg, 5.09 mol) and the resulting mixture was stirred at 20°C for 5 min. Triethylamine (0.94 Kg, 9.29 mol) was added to the reactor via an addition funnel and the resulting deep red solution was stirred at 25°C for 16 h. A solution of sodium carbonate (0.96 Kg, 9.06 mol) in water (7.04 L) was charged to the reaction mixture and stirred for 1 h at 20°C. The phases were split and the organic layer washed with brine (6 L) and concentrated at 40°C to a low stir volume. Dimethylacetamide (2 L) was charged to the reactor and concentration continued under full vacuum at 40°C for 1 h. The solution of tert-butyl 4-(tosyloxymethyl)piperidine-l -carboxylate (5) in dimethyl acetamide was held for further processing. Yield was assumed to be 100% with approximately

90% potency. A sample was pulled and concentrated to dryness for purity analysis. ¹ H NMR (400 MHz, CDCI₃) δ ppm 1 .02-1 .12 (m, 2H), 1.14 (s, 9H), 1 .59-1.64 (m, 2H), 1.75-1.87 (m, 1 H), 2.43 (s, 3H), 2.55-2.75 (m, 2H), 3.83 (d, J=6.7, 2H), 3.95-4.20 (b, 2H), 7.33 (d, 8.6, 2H), 7.76 (d, 8.2, 2H); ¹³C NMR (400 MHz, CDCI₃) δ ppm 21 .64, 28.15, 28.39, 35.74, 73.97, 79.50, 126.99, 127.84, 129.86, 132.84, 144.84, 154.63; LRMS 739.329 (2m+1 ).

Tert-butyl 4-((4-fluorobenzo[d]isoxazol-3-yloxy)methyl)piperidine-1-carboxylate (6): To a 20L jacketed reactor were charged dimethylacetamide (4.28 L), tert-butyl 4-(tosyloxymethyl)piperidine-1 -carboxylate (5) (1.68 Kg, 4.56 mol), 4-fluorobenzo[d]isoxazol-3-ol (4) (540 g, 3.51 mol), and potassium carbonate (960 g, 6.98 mol) resulting in a thick beige slurry. The reaction mixture was heated to 50°C and stirred for 20 h and then cooled to 20°C, followed by the addition of water (7.5 L) and ethyl acetate (5.37 L). After mixing for 15 min, the phases were settled and split. The organic layer was washed with water (5.37 L), sending the aqueous wash to waste. The organic mixture was distilled under vacuum with a maximum jacket temperature of 40°C until approximately 5 L remained in the reactor. Methanol (2.68 L) was added and the resulting solution concentrated under vacuum to about 3 L of a yellow oil. Methanol (2.68 L) was charged to the reactor and the resulting solution was stirred at 25°C for 15 min. Water (0.54 L) was added over 15 min resulting in a white slurry. The mixture was cooled to 15°C, stirred for 1 h and then filtered. The filter cake was washed with a solution of water (0.54 L) in methanol (2.14 L), then air dried for 30 min, transferred to a vacuum oven and dried at 40°C for 12 h. The desired product, (6) (746 g, 2.13 mol), was isolated in 61 % yield. ¹ H NMR (400 MHz, CDCI₃) δ ppm 1.23-1 .37 (m, 2H), 1 .45 (s, 9H), 1 .78-1 .88 (m, 2H), 2.04-2.17 (m, 1 H), 2.67-2.83 (m, 2H), 4.02-4.26 (m, 2H), 4.28 (d, 6.6, 2H), 6.89 (dd, J=8.6, 7.5, 1 H), 7.21 (d, J=9, 1 H), (td, 8.6, 4.9); LRMS 351.171 (m+1 ).

(R)-Tert-butyl 4-((4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazol-3-yloxy)methyl)piperidine-1-carboxylate (8): To a 20 L glass reactor with the jacket set to 20°C were charged (R)-tetrahydrofuran-3-ol (7) (297 g, 3.37 mol) and dimethylacetamide (5.1 L). 2.0 M sodium bis(trimethylsilyl)amide in THF (1.37 L, 2.74 mol) was slowly added via an addition funnel while maintaining a pot temperature less than 30°C. The resulting orange/red solution was stirred at 25°C for 30 min. Then, tert-butyl 4-((4-fluorobenzo[d]isoxazol-3-yloxy)methyl)piperidine-1 -carboxylate (6) (640.15 g, 1.83 mol) was charged and the reaction mixture was stirred at 25°C for 16 h. The reaction mixture was cooled to 20°C and water (6.4 L) was slowly added over 45 min maintaining a pot temperature of less than 35°C. Ethyl acetate (6 L) was added and the biphasic mixture was stirred for 15 min and then separated. The aqueous layer was back extracted with additional ethyl acetate (4 L). The combined organics were then washed with water (5 L) and a 20% brine solution (5 L). The organic mixture was concentrated under vacuum with the jacket temperature set to 40°C to approximately 3 L and held for further processing. Quantitative yield of the desired product, (8) (0.76 Kg, 1 .82 mol), in ethyl acetate was assumed. A sample was pulled and concentrated to dryness for purity analysis. ¹ H NMR (400 MHz, CDCI₃) δ ppm 1 .25-1.38 (m, 2H), 1 .44 (s, 9H), 1.76-1 .84 (m, 2H), 1 .89-1.97 (b, 1 H), 1 .99-2.12 (m, 1 H), 2.14-2.28 (m, 2H), 2.63-2.84 (m, 2H), 3.90-4.21 (m, 6H), 4.24 (d, J=6.3, 2H), 5.00-5.05 (m, 1 H), 6.48 (d, J=8.2, 1 H), 6.98 (d, J=8.6, 1 H), 7.37 (t, J=8.2, 1 H); LRMS 419.216 (m+1 ).

(R)-3-(Piperidin-4-ylmethoxy)-4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazole 4-methylbenzenesulfonate (9): To a 20L jacketed reactor charged ethyl acetate (6.1 L), (R)-tert-butyl 4-((4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazol-3-yloxy)methyl)piperidine-1 -carboxylate (8) (0.76 kg, 1 .82 mol) and p-toluenesulfonic acid monohydrate (0.413 kg, 2.17 mol) and stirred at 20°C for 30 min. The reactor jacket was heated from 20 to 65°C over

1 h and then held at 65°C for 16 h. The reactor was cooled to 15°C over 1 h and granulated for 2 h. The resulting slurry was filtered, the cake was washed with EtOAc (3 L) and then air dried on the filter for 30 min. The cake was transferred to a vacuum oven and dried at 40°C for 12 h. The desired product, (9) (854 g, 1.74 mol), was isolated in 96% yield (two steps). ¹ H NMR (400

MHz, CD₃OD) δ ppm 1.54-1 .67 (m, 2H), 2.04-2.18 (m, 3H), 2.19-2.36 (m, 2H), 2.33 (s, 3H), 3.01 -3.12 (m, 2H), 3.41-3.50 (m, 2H), 3.86-4.01 (m, 4H), 4.26 (d, J=6.3, 2H), 4.90 (s, 2H), 5.14-5.19 (m, 1 H), 6.72 (d, J=8.2, 1 H), 7.02 (d, J=8.6, 1 H), 7.21 (d, J=7.8, 2H), 7.48 (t, J=8.6, 1 H), 7.70 (d, J=8.2, 2H); LRMS 319.165 (m+1 ).

(R)-4-((4-((4-(Tetrahydrofuran-3-yloxy)benzo[d]isoxazol-3-yloxy)methyl)piperidin-1-yl)methyl)tetrahydro-2H-pyran-4-ol (11): To a

20L jacketed reactor were charged water (7.5 L) and sodium carbonate (0.98 kg); the mixture was stirred at 20°C until all solids had dissolved. Then (R)-3-(piperidin-4-ylmethoxy)-4-(tetrahydrofuran-3-yloxy)benzo[d]isoxazole 4-methylbenzenesulfonate (9) (750 g, 1 .53 mol) and ethyl acetate (6.0 L) were added to the reactor and stirred at 20°C for 30 min. The phases were split and the lower aqueous layer was back extracted twice with ethyl acetate (6.0 L and then 3.75 L). The organic layers were combined in the 20L reactor and washed twice with brine (3.0 L). The ethyl acetate solution was concentrated to under vacuum at 45°C to a low stir volume. Isopropyl alcohol (3.75 L) was added and concentration continued until 2 L remained in the reactor.

Additional isopropyl alcohol (2.75 L) was added and the mixture cooled to 25°C. To the reactor was charged 1 ,6-dioxaspiro[2.5]octane (10) (260 g, 2.29 mol) and the resulting solution heated to 50°C and stirred for 16 h. The reaction mixture was cooled to 30°C and water (15 L) was added over 60 min. Product crystallized from solution and the resulting slurry was cooled to 15°C over 1 h and then granulated for 4 h. The product was filtered and washed with water (3.75 L). The cake was blown dry with nitrogen for 30 min and then transferred to a vacuum oven and dried at 40°C for 12 h. The desired product, (11 ) (588 g, 1 .36 mol), was isolated in 89% yield.

¹ H NMR (400 MHz, CDCI₃) δ ppm 1 .41-1 .63 (m, 6H), 1.71 -1.81 (m, 2H), 1.81 -1.94 (m, 1 H), 2.17-2.26 (m, 2H), 2.33 (s, 2H), 2.4 (td, J=1 1.7, 2.3, 2H), 2.92 (d, J=1 1 .8, 2H), 3.46 (s, 1 H), 3.71-3.84 (m, 4H), 3.91 -4.10 (m, 4H), 4.24 (d, J=5.9, 2H), 5.03-5.08 (m, 1 H), 6.50 (d, J=8.2, 1 H), 7.00 (d, J=8.2, 1 H), 7.38 (t, J=8.2, 1 H);

¹³C NMR (400 MHz, CDCI₃) δ ppm 29.1 1 , 33.10, 35.20, 36.92, 36.96, 56.15, 63.93, 67.14, 67.46, 68.27, 72.94, 74.06, 78.37, 103.17, 105.15, 131.71 , 152.71 , 166.02, 166.28;

LRMS 433.232 (m+1 ).

Example 2: Synthesis of iR)-4-ii4-i(4-itetrahvdrofuran-3-yloxy)benzord1isoxazol-3-yloxy)methyl)piperidin-1 -yl)methyl)tetrahvdro- 2H-pyran-4-ol

5-Hydroxy-2,2-dimethyl-benzo[1,3]dioxin-4-one: Thionyl chloride (83.8 g, 0.71 mol) was slowly added to a solution of 2,6-dihydroxy-benzoic acid (77 g, 0.5 mol), acetone (37.7 g, 0.65 mol) and DMAP (3.1 g, 0.025 mol) in dimethoxyethane (375 mL). The mixture was stirred at RT for 7 h. The residue obtained after concentration under reduced pressure was dissolved in ethyl

acetate and washed with water and aqueous saturated sodium bicarbonate solution. The organic layer was dried (Na₂S0₄) and concentrated to afford 79 g desired product as a red solid (81 % yield). ¹ H NMR (400 MHz, CDCI₃) δ ppm 1 .68 (s, 6H), 6.37 (dd, J=8, 0.8, 11-1) 6.56 (dd, J=8, 0.8, 1 H), 7.34 (t, J=8, 1 H), 10.27( brs, 1 H).

2,2-Dimethyl-5-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[1,3]dioxin-4-one:

Diethyl azodicarboxylate (130.5 g, 0.75 mol) was added in a dropwise fashion to a mixture of 5-hydroxy-2,2-dimethyl-benzo[1 ,3]dioxin-4-one (100 g, 0.51 mol), triphenylphosphine (196.5 g, 0.75 mol), and (S)-tetrahydro-furan-3-ol (44 g, 0.5 mol) in 600 ml. of anhydrous THF. The resulting mixture was stirred at RT for 18 h. The solvent was removed under reduced pressure and the crude material was purified on a silica gel flash column, eluting with petroleum ether/ ethyl acetate (15:1 -> 3:1 ). 86 g (65% yield) of product was isolated as a colorless oil. ¹ H NMR (400 MHz, CDCI₃) δ ppm 1.67 (s, 6H), 2.30 (m, 2H), 4.2 (m, 4H) 4.97 (m, 1 H), 6.49 (d, J=8.4, 1 H) 6.51 (d, J=8.4, 1 H), 7.39 (t,

J=8.4, 1 H).

2-Hydroxy-6-[(R)-(tetrahydro-furan-3-yl)oxy]-benzoic acid methyl ester: Potassium carbonate (134.8 g, 0.98 mol) was added to a solution of 2,2-dimethyl-5-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[1 ,3]dioxin-4-one (86 g, 0.33 mol) in 1 L methanol. The mixture was stirred at RT for 2 h, then concentrated in vacuo. The residue was dissolved in ethyl acetate and washed with aqueous ammonium chloride solution. The organic layer was dried (Na₂S0₄) and concentrated to afford 72 g of the product as a yellow solid (92% yield). ¹ H NMR (400 MHz, CDCI₃) δ ppm 2.20 (m, 2H), 3.99 (s, 3H), 4.80(m, 4H). 4.94 (m, 1 H), 6.31 (dd, J=8.4, 0.8, 1 H), 6.59 (dd, J=8.4, 0.8, 1 H), 7.30 (t, J=8.4, 1 H).

2,N-Dihydroxy-6-[(R)-(tetrahydro-furan-3-yl)oxy]-benzamide: Potassium carbonate (121 g. 0.867mmol) was added portionwise to a solution of hydroxylamine sulfate (120 g, 0.732 mol) in 360 ml. of water at 0°C. After stirring for 30 min, sodium sulfite (3.74 g, 0.029 mol) and a solution of 2-hydroxy-6-[(R)-(tetrahydro-furan-3-yl)oxy]-benzoic acid methyl ester (35 g, 0.146 mol) in 360 ml. of methanol were added and the mixture was stirred at 50°C for 30 h. Methanol was removed from the cooled reaction mixture under reduced pressure and the resulting aqueous layer was acidified with 2N HCI. The aqueous layer was extracted with ethyl acetate and the organic layer was dried (Na₂S0₄) and concentrated to afford 25 g (76% yield ) of the product as a yellow solid. ¹ H NMR (400 MHz, CDCI₃) δ ppm 2.00 (m, 1 H), 2.15 (m, 1 H), 3.80 (m, 4H), 5.05 (m, 1 H), 6.48 (d, J=8, 1 H), 6.49 (d, J=8, 1 H), 7.19 (t, J=8, 1 H), 10.41 (brs, 1 H), 1 1.49 (brs, 1 H); LRMS m/z 239 (m+1 ).

4-[(R)-(Tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-ol: A solution of 2, N-dihydroxy-6-[(R)-(tetrahydro-furan-3-yl)oxy]-benzamide (25 g, 0.105 mol) in 250 ml. of THF was heated to 50°C. Carbonyl diimidazole was added portionwise and the resulting mixture was stirred at 50°C for 14 h. After cooling to RT, 100 ml. of 2N HCI was added and the aqueous layer was extracted with ethyl acetate. The combined organic layers were then extracted three times with 10% aqueous potassium carbonate. The potassium carbonate aqueous extracts were washed with ethyl acetate and then acidified to pH 2 – 3 with 2N HCI. The acidified aqueous layer was extracted with ethyl acetate. The ethyl acetate extracts were washed with brine, dried (Na₂S0₄) and concentrated to afford 20 g of product as a yellow solid (43% yield). ¹ H NMR (400 MHz, CDCI₃) δ ppm 2.20 (m, 2H), 3.89 (m, 1 H), 4.01 (m, 3H), 5.05 (m, 1 H), 6.48 (d, J=7.6, 1 H). 6.92 (d, J=7.6, 1 H), 7.37 (t, J=7.6, 1 H); LRMS m/z 222 (m+1 ).

4-{4-[(R)-(Tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-yloxymethyl}-piperidine-1-carboxylic acid tert-butyl ester: Diethyl azodicarboxylate (15.6 g, 0.09 mol) was added to a mixture of 4-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-ol (10 g, 0.045 mol), 4-hydroxymethyl-piperidine-1 -carboxylic acid tert-butyl ester (1 1.6 g, 0.054 mol) and triphenylphosphine (23.5 g, 0.09 mol) in 300 mL THF. After the addition was complete the mixture was heated at reflux for 18 h. After concentration in vacuo, the crude product was purified on a silica gel flash column, eluting with petroleum ether/ ethyl acetate (15:1 -» 5:1 ) to afford 22 g of the product as an oil (51 % yield). ¹ H NMR (400 MHz, CDCI₃) δ ppm 1.25 (m, 2H), 1.39 (s, 9H), 1.76 (m, 2H), 1.99 (m, 1 H). 2.15 (m, 2H), 2.70 (bt, J=1 1.6, 2H), 3.95 (m, 4H). 4.13 (m, 2H). 4.34 (d J=6.4, 2H), 4.98 (m, 1 H), 6.43 (d, J=8, 1 H), 6.93 (d, J=8, 1 H), 7.31 (t, J=8, 1 H).

3-(Piperidin-4-ylmethoxy)-4-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazole: A 0°C solution of 4-{4-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-yloxymethyl}-piperidine-1 -carboxylic acid tert-butyl ester in 500 mL ether was treated with a saturated solution of HCI (g) in 200 mL ether. After addition was complete, the mixture was warmed to RT and stirred for 16 h. The reaction mixture was filtered. The white solid was washed with ethyl acetate followed by ether and dried to yield 15 g (81 % yield) of the desired product as a white solid. ¹ H NMR (400 MHz, CD₃OD) 5 ppm 1 .51 – 1.69 (m, 2 H) 2.04 – 2.19 (m, 3 H) 2.22 – 2.37 (m, 2 H) 2.99 – 3.14 (m, 2 H) 3.40 – 3.51 (m, 2 H) 3.85 – 4.02 (m, 4 H) 4.25 – 4.31 (m, 2 H) 5.17 (td, J= >1^ , 1 .56 Hz, 1 H) 6.72 (d, J=8.00 Hz, 1 H) 7.01 (d, J=8.59 Hz, 1 H) 7.47 (t, J=8.20 Hz, 1 H); LRMS m/z 319 (m+1 ).

4-(4-{4-[(R)-(Tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazol-3-yloxymethyl}-piperidin-1-ylmethyl)-tetrahydro-pyran-4-ol: 1 ,6-Dioxa-spiro[2.5]octane (Focus Synthesis; 9.7 g, 0.084 mol) and triethylamine (8.6 g, 0.084 mol) were added to a solution of 3-(piperidin-4-ylmethoxy)-4-[(R)-(tetrahydro-furan-3-yl)oxy]-benzo[d]isoxazole (15 g, 0.042 mol) in 200 mL methanol. The resulting solution was heated at reflux for 18 h. The cooled mixture was concentrated and ethyl acetate and water were added to the residue. The layers were separated and the organic extracts were washed with brine, dried (Na₂S0₄) and concentrated to provide 17 g crude product as a yellow oil. The crude material was purified by prep HPLC to afford 10 g of the desired product as a white solid. (50% yield).

¹ H NMR (400 MHz, CDCI₃) δ ppm 1.41 -1.63 (m, 6H), 1.71-1.81 (m, 2H), 1 .81 -1 .94 (m, 1 H), 2.17-2.26 (m, 2H), 2.33 (s, 2H), 2.4 (td, J=1 1 .7, 2.3, 2H), 2.92 (d, J=1 1.8, 2H), 3.46 (s, 1 H), 3.71-3.84 (m, 4H), 3.91-4.10 (m, 4H), 4.24 (d, J=5.9, 2H), 5.03-5.08 (m, 1 H), 6.50 (d, J=8.2, 1 H), 7.00 (d, J=8.2, 1 H), 7.38 (t, J=8.2, 1 H);

¹³C NMR (101 MHz, CDCI₃) δ ppm 29.1 1 , 33.10, 35.20, 36.92, 36.96, 56.15, 63.93, 67.14, 67.46, 68.27, 72.94, 74.06, 78.37, 103.17, 105.15, 131.71 , 152.71 , 166.02, 166.28.

PAPER

Two Routes to 4-Fluorobenzisoxazol-3-one in the Synthesis of a 5-HT₄Partial Agonist

Daniel W. Widlicka^*^†, John C. Murray^†, Karen J. Coffman^†, Chunguang Xiao^‡, Michael A. Brodney^†, Joseph P. Rainville^†, and Brian Samas^†

^† Groton Laboratories, Worldwide Research & Development, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340,United States

^‡ Porton Fine Chemical, 1 Fine Chemical Zone, Chongqing Chemical Industrial Park, Changshou, Chongqing 401221China

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00389

Publication Date (Web): February 2, 2016

*E-mail: daniel.w.widlicka@pfizer.com.

http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00389

A potent 5-HT₄ partial agonist, 1 (PF-04995274), targeted for the treatment of Alzheimer’s disease and cognitive impairment, has been prepared on a multi-kilogram scale. The initial synthetic route, that proceeded through a 4-substituted 3-hydroxybenzisoxazole core, gave an undesired benzoxazolinone through a Lossen-type rearrangement. Route scouting led to two new robust routes to the desired 4-substituted core. Process development led to the efficient assembly of the API on a pilot plant scale under process-friendly conditions with enhanced throughput. In addition, crystallization of a hemicitrate salt of the API with pharmaceutically beneficial properties was developed to enable progression of clinical studies.

REFERNCES

Noguchi, H.; Waizumi, N. Preparation of benzisoxazole derivatives for treatment of 5-HT4 mediated disorders. PCT Int. Appl. WO/2011/101774 A1, 20110825

////////PF-04995274, PF 04995274, PFIZER, Alzheimer’s type dementia, PHASE 1

c1cc2c(c(c1)O[C@@H]3CCOC3)c(no2)OCC4CCN(CC4)CC5(CCOCC5)O

New TRPV1 Antagonist From Neurogen Corporation

February 1, 2016 3:50 am / Leave a comment

MK ? NGD?

MK 2295; NGD 8243 may be???????

CAS 878811-00-8 FREE FORM

Molecular Formula:	C₂₇H₃₁FN₆O₂
Molecular Weight:	490.572443 g/mol

6-[(3R)-4-[6-(4-fluorophenyl)-2-[(2R)-2-methylpyrrolidin-1-yl]pyrimidin-4-yl]-3-methylpiperazin-1-yl]-5-methylpyridine-3-carboxylic acid

6-{4-[6-(4-Fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidin-4-yl]-3-(R)-methyl-piperazin-1-yl}-5-methyl-nicotinic acid

3-Pyridinecarboxylic acid, 6-[(3R)-4-[6-(4-fluorophenyl)-2-[(2R)-2-methyl-1-pyrrolidinyl]-4-pyrimidinyl]-3-methyl-1-piperazinyl]-5-methyl-

Neurogen Corp INNOVATOR

MESYLATE

CAS 1855897-95-8

6-((R)-4-(6-(4-Fluorophenyl)-2-((R)-2-methylpyrrolidin-1-yl)pyrimidin-4-yl)-3-methylpiperazin-1-yl)-5-methylnicotinic acid methanesulfonic acid salt

white solid. ¹H NMR (CD₃OD, 400 MHz) δ 1.37 (d, 3H, J= 6.4 Hz), 1.48 (d, 3H, J = 6.7 Hz), 1.84 (m, 1H), 2.09 (m, 1H), 2.17–2.25 (m, 2H), 2.42 (s, 3H), 2.66 (s, 3H), 3.10 (dt, 1H, J = 12.3 and 3.3 Hz), 3.28 (dd, 1H, J = 13.1 and 3.7 Hz), 3.65–3.72 (m, 3H), 3.78 (m, 1H), 3.87 (m, 1H), 4.49 (m, 1H), 4.63 (m, 3H), 4.96 (br m, 1H), 6.61 (s, 1H), 7.32 (m, 2H), 7.82 (m, 2H), 8.05 (m, 1H), 8.69 (d, 1H, J = 1.9 Hz);

¹³C NMR (CD₃OD, 125 MHz) δ 19.4, 24.5, 33.5, 39.6, 41.5, 48.6, 50.0, 50.9, 54.1, 56.9, 94.8, 117.3 (d, J = 22.5 Hz), 122.1, 125.0, 130.1 (d, J = 3.3 Hz), 131.8 (d, J = 8.9 Hz), 142.1, 148.7, 153.1, 153.3, 162.4, 165.4, 166.4, (d, J = 251.3 Hz), 168.8;

¹⁹F NMR (CD₃OD, 470 MHz) δ −108.6.

Anal. Calcd For C₂₈H₃₅FN₆O₅S: C, 57.32; H, 6.01; N, 14.32. Found: C, 57.34; H, 6.13; N, 14.29.

Activated by a wide range of stimuli such as capsaicin, acid, or heat, the transient receptor potential vanilloid-1 (TRPV1) has been identified as a potential treatment for chronic pain.TRPV1 is a highly characterized member of the TRP cation channel family believed to be involved in a number of important biological roles and plays a role in the transmission of pain.TRPV1 activation inhibits the transition of pain signals from the periphery to the central nervous system (CNS), leading to the possible development of analgesic and anti-inflammatory agents. TRPV1 antagonists have also been evaluated in multiple clinical trials where hyperthermic effects seen preclinically are also observed in humans

PATENT

http://www.google.com.na/patents/US20110003813

6-{4-[6-(4-Fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidin-4-yl]-3-(R)-methyl-piperazin-1-yl}-5-methyl-nicotinic acid 1. 1-(5-Bromo-3-methyl-pyridin-2-yl)-3-(R)-methyl-piperazine

Heat a solution of 2,5-dibromo-3-methyl-pyridine (Chontech Inc., Waterford, Conn.) (2.0 g, 7.97 mmol), (R)-2-methyl-piperazine (ChemPacific Corp., Baltimore, Md.; 3.2 g, 31.9 mmol) in DMA at 130° C. for 16 h. Partition the reaction mixture between water and EtOAc. Wash the EtOAc layer with water (1×) and brine (1×), dry (Na₂SO₄) and concentrate under reduced pressure to give 1-(5-bromo-3-methyl-pyridin-2-yl)-3-(R)-methyl-piperazine as a solid.

2. 2,4-dichloro-6-(4-fluorophenyl)pyrimidine

Dissolve 4-fluorobromobenzene (8.75 g, 0.05 moles) in anhydrous ether (80 mL) under nitrogen atmosphere and cool to −78° C. Add dropwise 1.6 M n-BuLi (34 mL, 0.055 moles) and stir at −78° C. for 45 min. Dissolve 2,4-dichloropyrimidine (7.45 g, 0.05 moles) in Et₂O (100 mL) and add dropwise to the reaction mixture. Warm the reaction mixture to −30° C. and stir at this temperature for 30 min followed by 0° C. for 30 min. Quench the reaction mixture with AcOH (3.15 mL, 0.055 moles) and water (0.5 mL, 0.027 moles) dissolved in THF (5.0 mL). Add dropwise a THF (40 mL) solution of DDQ (11.9 g, 0.053 moles) to the reaction mixture. Bring the reaction mixture to room temperature and stir at room temperature for 30 min. Cool the reaction mixture to 0° C., add 3.0 N aq. NaOH (35 mL) and stir for 30 min. Decant the organic layer from the reaction mixture and wash the brown solid with Et₂O (3×100 mL). Combine the organic layers, wash several times with saturated NaCl solution and dry with MgSO₄. Filter and evaporate under vacuum to afford a brown colored solid. Purify by flash column chromatography using 5% EtOAc/hexane to afford the title product as a white solid.

3. 4-[4-(5-Bromo-3-methyl-pyridin-2-yl)-2-(R)-methyl-piperazin-1-yl]-2-chloro-6-(4-fluoro-phenyl)-pyrimidine

Heat a mixture of 2,4-dichloro-6-(4-fluoro-phenyl)-pyrimidine (6.0 g, 24.7 mmol), 1-(5-bromo-3-methyl-pyridin-2-yl)-3-(R)-methyl-piperazine (7.0 g, 25.9 mmol) and K₂CO₃(6.8 g, 49.4 mmol) in DMA at 60° C. for 16 h. Partition the mixture between EtOAc and water, dry (Na₂SO₄) the organic layer and concentrate under reduced pressure. Purify with flash silica gel column eluting with 15% EtOAc/hexanes. Concentrate under reduced pressure to give the title compound.

4. 4-[4-(5-Bromo-3-methyl-pyridin-2-yl)-2-(R)-methyl-piperazin-1-yl]-6-(4-fluoro-phenyl)-2-(2-(R)-methyl-pyrrolidin-1-yl)-pyrimidine

Heat a mixture of 4-[4-(5-bromo-3-methyl-pyridin-2-yl)-2-(R)-methyl-piperazin-1-yl]-2-chloro-6-(4-fluoro-phenyl)-pyrimidine (7.7 g, 16.2 mmol), (R)-2-methylpyrrolidine hydrobromide [prepared essentially as described by Nijhuis et. al. (1989) J. Org. Chem. 54(1):209] (3.5 g, 21.1 mmol) and K₂CO₃(5.1 g, 37.3 mmol) in DMA at 110° C. for 16 h. Partition the mixture between EtOAc and water, dry (Na₂SO₄) the organic layer and concentrate under reduced pressure. Purify with flash silica gel column eluting with 10% EtOAc/hexanes. Concentrate under reduced pressure to give the title compound.
5. 6-{4-[6-(4-Fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidin-4-yl]-3-(R)-methyl-piperazin-1-yl}-5-methyl-nicotinonitrile
To a mixture of 4-[4-(5-bromo-3-methyl-pyridin-2-yl)-2-(R)-methyl-piperazin-1-yl]-6-(4-fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidine (700 mg, 1.33 mmol) and Zn(CN)₂(94 mg, 0.799 mmol) in DMF, add Pd(PPh₃)₄(77 mg, 0.067 mmol). Purge the reaction mixture for 10 min with dry N₂. Heat the stirring reaction mixture overnight at 80° C., cool to room temperature and partition between water and EtOAc. Dry the solution (Na₂SO₄), concentrate under reduced pressure. Purify the residue by flash column eluting with EtOAc-Hexanes (1:1) to afford the title compound as a white solid.
6. 6-{4-[6-(4-Fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidin-4-yl]-3-(R)-methyl-piperazin-1-yl}-5-methyl-nicotinic acid
Heat a solution of 6-{4-[6-(4-fluoro-phenyl)-2-(2-methyl-pyrrolidin-1-yl)-pyrimidin-4-yl]-3-(R)-methyl-piperazin-1-yl}-5-methyl-nicotinonitrile (100 mg, 0.212 mmol) in 12 M HCl for 3 hours at 90° C. Concentrate the mixture under reduced pressure. Add a small amount of water, adjust the pH to 6-7, and collect the resulting white precipitate to afford the title compound as a off-white solid. ¹H NMR (300 MHz, DMSO-d₆): δ 1.24 (m, 6H, 2×CH₃))_;1.61 (m, 1H,); 1.84 (m, 1H); 1.98 (m, 2H); 2.34 (s, 3H, Ar—CH₃); 2.91 (m, 1H); 3.08 (m, 1H); 3.26 (m, 2H); 3.56 (m, 2H); 3.74 (m, 1H); 4.21 (m, 1H); 4.35 (m, 1H); 4.74 (m, 1H); 6.57 (s, 1H); 7.26 (m, 2H); 7.91 (d, 1H, J=3 Hz); 8.15 (m, 2H); 8.60 (d, 1H, J=3 Hz).

END…………………

MESYLATE NMR

¹H NMR (CD₃OD, 400 MHz) δ 1.37 (d, 3H, J= 6.4 Hz), 1.48 (d, 3H, J = 6.7 Hz), 1.84 (m, 1H), 2.09 (m, 1H), 2.17–2.25 (m, 2H), 2.42 (s, 3H), 2.66 (s, 3H), 3.10 (dt, 1H, J = 12.3 and 3.3 Hz), 3.28 (dd, 1H, J = 13.1 and 3.7 Hz), 3.65–3.72 (m, 3H), 3.78 (m, 1H), 3.87 (m, 1H), 4.49 (m, 1H), 4.63 (m, 3H), 4.96 (br m, 1H), 6.61 (s, 1H), 7.32 (m, 2H), 7.82 (m, 2H), 8.05 (m, 1H), 8.69 (d, 1H, J = 1.9 Hz);

¹⁹F NMR (CD₃OD, 470 MHz) δ −108.6.

PATENT

http://www.google.ga/patents/WO2006026135

Scheme 1

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 14

Scheme 15

Scheme 16

Scheme 17

Scheme 18

Scheme 19

Scheme 20

6-{4-[6~(4-Fluoro-phenyl)-2-(2~methyl-pyrrolidin-l-yl)-pyrimidin-4-yl]-3-(R)-met}τyl- piperazin-l-yl}-5-methyl-nicotinic acid

Heat a solution of 6-{4-[6-(4-fluoro-phenyl)-2-(2-methyl-pyrrolidin-l-yl)-pyrimidin-4-yl]- 3-(R)-methyl-piperazin-l-yl}-5-methyl-nicotinonitrile (100 mg, 0.212 mmol) in 12 M HCl for 3 hours at 9O⁰C. Concentrate the mixture under reduced pressure. Add a small amount of water, adjust the pH to 6-7, and collect the resulting white precipitate to afford the title compound as a off-white solid. ¹H NMR (300 MHz, DMSO-d₆): δ 1.24 (m, 6H, 2xCH₃)); 1.61 (m, 1Η,); 1.84 (m, 1Η); 1.98 (m, 2Η); 2.34 (s, 3H, Ar-CH₃); 2.91 (m, 1Η); 3.08 (m, 1Η); 3.26 (m, 2Η); 3.56 (m, 2H); 3.74 (m, IH); 4.21 (m, IH); 4.35 (m, IH); 4.74 (m, IH); 6.57 (s, IH); 7.26 (m, 2H); 7.91 (d, IH, J = 3Hz); 8.15 (m, 2H); 8.60 (d, IH, J = 3Hz).

PAPER

Development of a Multikilogram Scale Synthesis of a TRPV1 Antagonist

Jeffrey T. Kuethe^*, Michel Journet, Zhihui Peng, Dalian Zhao, Arlene McKeown, and Guy R. Humphrey

Department of Process Chemistry, Merck & Co., Inc., Rahway, New Jersey 07065, United States

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00388

Publication Date (Web): January 13, 2016

*E-mail: Jeffrey_Kuethe@merck.com.

Abstract

A highly efficient, regioselective five-step synthesis of the TRPV1 antagonist 1 is described. The coupling of piperazine 7 with dichloropyrimidine 8 proceeded via a regioselective Pd-mediated amination affording product 11 in excellent yield. Conversion of the penultimate product 14 afforded 1 through formation of a magnesium ate complex and trapping with CO₂.

http://pubs.acs.org/doi/suppl/10.1021/acs.oprd.5b00388

http://pubs.acs.org/doi/suppl/10.1021/acs.oprd.5b00388/suppl_file/op5b00388_si_001.pdf

Patent	Submitted	Granted
Substituted biaryl piperazinyl-pyridine analogues [US7662830]	2006-06-08	2010-02-16
SUBSTITUTED BIARYL PIPERAZINYL-PYRIDINE ANALOGUES [US2011003813]	2011-01-06

Blum, C. A.; Brielmann, H.; Chenard, B. L.; Zheng, X. Preparation of substituted biaryl piperazinyl-pyridine analogues as capsaicin modulators. PCT Int. Appl. WO 2006026135 A2 20060309, 2006.

Neurogen Corporation, a Subsidiary of Ligand Pharmaceuticals Inc., 11119 North Torrey Pines Road, Suite 200, La Jolla, CA 92037, U.S.A.

Neurogen and Merck Agreement for Next-Generation Pain Drugs Consummated

Source	Press Release
Company	Neurogen, Merck & Co
Tags	Central Nervous System, Research Collaboration
Date	January 16, 2004

Branford, CT — January 16, 2004 — Neurogen Corporation (Nasdaq: NRGN) today announced that it has consummated its previously announced alliance with Merck & Co ., Inc. (NYSE: MRK) to discover and develop next-generation drugs for the treatment of pain. The deal received clearance from the Federal Trade Commission under the Hart-Scott-Rodino Act and the companies have now commenced the collaboration. The alliance, announced December 1, 2003, enables Merck , through a subsidiary, and Neurogen to pool drug candidates targeting the vanilloid receptor (VR1 ), a key integrator of pain signals in the nervous system, and combine their ongoing VR1 programs to form a global research and development collaboration.

With consummation of the deal, Neurogen has received $30 million from Merck , including a $15 million up-front license fee payment and a $15 million equity investment in Neurogen common stock. Under the agreement, Merck has purchased 1,783,252 shares of newly issued Neurogen common stock at $8.41 per share, the average market price per share for the 25 trading days preceding regulatory clearance. Merck ‘s new shareholder position represents approximately 9% of Neurogen ‘s 19,873,464 total shares outstanding.

About Neurogen

Neurogen Corporation targets new small molecule drugs to improve the lives of patients suffering from disorders with significant unmet medical need. Neurogen has generated a portfolio of compelling new drug candidates through its Accelerated Intelligent Drug Discovery (AIDD(TM)) system, its expertise in cellular functional assays, and its depth in medicinal chemistry. Neurogen conducts its research and development independently and, when advantageous, collaborates with world-class pharmaceutical companies to obtain additional resources and to access complementary expertise.

////////

n1c(nc(cc1c2ccc(cc2)F)N3CCN(C[C@H]3C)c4ncc(cc4C)C(=O)O)N5CCC[C@H]5C

5-Bromo-1-methyl-1H-imidazole-4-carbonitrile

January 30, 2016 2:51 pm / Leave a comment

Source: 5-Bromo-1-methyl-1H-imidazole-4-carbonitrile

Fresolimumab

January 30, 2016 4:23 am / 1 Comment on Fresolimumab

Fresolimumab
GC 1008, GC1008
UNII-375142VBIA

cas 948564-73-6

Structure

immunoglobulin G4, anti-(human transforming growth factors beta-1, beta-2 (G-TSF or cetermin) and beta-3), human monoclonal GC-1008 γ4 heavy chain (134-215′)-disulfide with human monoclonal GC-1008 κ light chain, dimer (226-226”:229-229”)-bisdisulfide
immunoglobulin G4, anti-(transforming growth factor β) (human monoclonal GC-1008 heavy chain), disulfide with human monoclonal GC-1008 light chain, dimer

For Idiopathic Pulmonary Fibrosis, Focal Segmental Glomerulosclerosis,and Cancer

An anti-TGF-beta antibody in phase I clinical trials (2011) for treatment-resistant primary focal segmental glomerulosclerosis.

A pan-specific, recombinant, fully human monoclonal antibody directed against human transforming growth factor (TGF) -beta 1, 2 and 3 with potential antineoplastic activity. Fresolimumab binds to and inhibits the activity of all isoforms of TGF-beta, which may result in the inhibition of tumor cell growth, angiogenesis, and migration. TGF-beta, a cytokine often over-expressed in various malignancies, may play an important role in promoting the growth, progression, and migration of tumor cells.

Fresolimumab (GC1008) is a human monoclonal antibody^[1] and an immunomodulator. It is intended for the treatment of idiopathic pulmonary fibrosis (IPF), focal segmental glomerulosclerosis, and cancer^[2]^[3] (kidney cancer and melanoma).

It binds to and inhibits all isoforms of the protein transforming growth factor beta (TGF-β).^[2]

History

Fresolimumab was discovered by Cambridge Antibody Technology (CAT) scientists^[4] and was one of a pair of candidate drugs that were identified for the treatment of the fatal condition scleroderma. CAT chose to co-develop the two drugs metelimumab (CAT-192) and fresolimumab with Genzyme. During early development, around 2004, CAT decided to drop development of metelimumab in favour of fresolimumab.^[5]

In February 2011 Sanofi-Aventis agreed to buy Genzyme for US$ 20.1 billion.^[6]

As of June 2011 the drug was being tested in humans (clinical trials) against IPF, renal disease, and cancer.^[7]^[8] On 13 August 2012, Genzyme applied to begin a Phase 2 clinical trial in primary focal segmental glomerulosclerosis^[9] comparing fresolimumab versus placebo.

As of July 2014, Sanofi-Aventis continue to list fresolimumab in their research and development portfolio under Phase II development.^[10]

References

1 WHO Drug Information

2 National Cancer Institute: Fresolimumab

3 Statement On A Nonproprietary Name Adopted By The USAN Council – Fresolimumab
4 Grütter, Christian; Wilkinson, Trevor; Turner, Richard; Podichetty, Sadhana; Finch, Donna; McCourt, Matthew; Loning, Scott; Jermutus, Lutz; Grütter, Markus G. (2008-12-23). “A cytokine-neutralizing antibody as a structural mimetic of 2 receptor interactions”. Proceedings of the National Academy of Sciences 105 (51): 20251–20256. doi:10.1073/pnas.0807200106. ISSN 0027-8424. PMC 2600578. PMID 19073914.
5 http://www.independent.co.uk/news/business/news/cat-may-abandon-skin-drug-after-trial-results-disappoint-569445.html
6 http://www.bbc.co.uk/news/business-12477750
7 http://www.genengnews.com/gen-news-highlights/scientists-trigger-white-fat-to-become-brown-fat-like-to-treat-obesty-and-type-2-diabetes/81245389/
8 Clinicaltrials.gov for Fresolimumab
9 http://clinicaltrials.gov/show/NCT01665391
10 http://en.sanofi.com/rd/rd_portfolio/rd_portfolio.aspx

Fresolimumab
Monoclonal antibody
Type	Whole antibody
Source	Human
Target	TGF beta 1, 2 and 3
Clinical data
Legal status	Investigational
Identifiers
CAS Number	948564-73-6
ATC code	None
ChemSpider	none
KEGG	D09620
Chemical data
Formula	C₆₃₉₂H₉₉₂₆N₁₆₉₈O₂₀₂₆S₄₄
Molar mass	144.4 kDa

////////////

Monoclonal antibodies for the immune system

Immune system (“-l(i[m])-“)

Human (“-limu-“)	immunosuppression: Abrilumab Adalimumab Anifrolumab Atorolimumab Belimumab Brodalumab Carlumab Dupilumab Durvalumab Eldelumab Fresolimumab Golimumab Lerdelimumab Lirilumab Mavrilimumab Metelimumab Morolimumab Namilumab Oxelumab§ Placulumab Sarilumab Sifalimumab Tabalumab Ulocuplumab Varlilumab immune activation: Ipilimumab Nivolumab Pembrolizumab Tremelimumab Urelumab other: Bertilimumab Zanolimumab

Mouse (“-limo-“)	Afelimomab Elsilimomab Faralimomab Gavilimomab Inolimomab Maslimomab Nerelimomab Odulimomab Telimomab aritox Vepalimomab Zolimomab aritox

Chimeric (“-lixi-“)	Basiliximab Clenoliximab Galiximab Gomiliximab Infliximab Keliximab Lumiliximab Priliximab Teneliximab Vapaliximab

Humanized (“-lizu-“)	immunosuppressive: Aselizumab Apolizumab Benralizumab^† Cedelizumab Certolizumab pegol Daclizumab Eculizumab Efalizumab Epratuzumab Erlizumab Etrolizumab Fontolizumab Itolizumab Lampalizumab Ligelizumab Lulizumab pegol Mepolizumab Mogamulizumab Natalizumab Ocrelizumab Omalizumab Ozoralizumab Pascolizumab Pateclizumab Pembrolizumab Pexelizumab Pidilizumab PRO 140^† Reslizumab Rontalizumab Rovelizumab Ruplizumab Quilizumab Samalizumab Siplizumab Talizumab Teplizumab Tocilizumab Toralizumab Tregalizumab Vatelizumab Vedolizumab Visilizumab TGN1412^§ non-immunosuppressive: Ibalizumab^†

Chimeric + humanized (“-lixizu-“)	Otelixizumab

Interleukin (“-k(i[n])-“)

Human (“-kinu-“)	Briakinumab Canakinumab Fezakinumab Fletikumab Guselkumab Secukinumab Sirukumab Tralokinumab Ustekinumab

Humanized (“-kizu-“, “-kinzu-“)	Anrukinzumab Clazakizumab Enokizumab Gevokizumab Ixekizumab Lebrikizumab Olokizumab Perakizumab Tildrakizumab

Inflammatory lesions (“-les-“)

Mouse (“-leso-“)	Besilesomab Fanolesomab^‡ Lemalesomab Sulesomab

^#WHO-EM
^‡Withdrawn from market
Clinical trials:
- ^†Phase III
- ^§Never to phase III

v t e Index of the immune system

Description	Physiology cells autoantigens autoantibodies complement surface antigens IG receptors

Disease	Allergies Immunodeficiency Immunoproliferative immunoglobulin disorders Hypersensitivity and autoimmune disorders Neoplasms and cancer

Treatment	Procedures Drugs antihistamines immunostimulants immunosuppressants monoclonal antibodies

What was the drug in Clinical Trial Tragedy In France Jan 2016

January 23, 2016 12:22 pm / 2 Comments on What was the drug in Clinical Trial Tragedy In France Jan 2016

3-(1-(cyclohexyl(methyl)carbamoyl)-1H-imidazol-4-yl)pyridine 1-oxide.png

BIA 10-2474

cas 1233855-46-3

3-(1-(cyclohexyl(methyl)carbamoyl)-1H-imidazol-4-yl)pyridine 1-oxide

1H-Imidazole-1-carboxamide, N-cyclohexyl-N-methyl-4-(1-oxido-3-pyridinyl)-

C₁₆ H₂₀ N₄ O_2, 300.36

Bial-Portela & Ca. S.A.

BIA 10-2474 is an experimental fatty acid amide hydrolase inhibitor^[1] developed by the Portuguese pharmaceutical company Bial-Portela & Ca. SA. The drug was developed to relieve pain,^[2]^[3] to ease mood and anxiety problems, and to improve movement coordination linked to neurodegenerative illnesses.^[4] It interacts with the human endocannabinoid system.^[5]^[6] It has been linked to severe adverse events affecting 5 patients in a drug trial in Rennes, France, and at least one death, in January 2016.^[7]

Synthesis

WO 2014017938

BIAL – PORTELA & Cª, S.A.

Example 5. 3-(l-(cyclohexyl(methyl)carbamoyl-lfl-imidazol-4-yl)pyridine l-oxide (compound A)

C₁₆H₂₀N₄O C16H20N4O2

MW 284,36 MW 300,36

To a solution of N-cyclohexyl-N-methyl-4-(pyridm-3-yl)-lH-imidazole-l-carboxamide in dichioromethane at 25°C was added peracetic acid (38%; the concentration is not critical, and may be varied) in a single portion. The reaction mixture was then maintained at 25°C for at least 20 h, whereupon the reaction was washed four times with water (in some embodiments, the water for the extraction step may be supplemented with a small amount (e.g. 1%) of acetic acid, which helps to promote product solubility in the DCM). The dichioromethane solution was then filtered prior to diluting with 2-propanol. Dichioromethane (50%) was then distilled off under atmospheric pressure, whereupon, 2-propanol was charged at the same rate as the distillate was collected. The distillation was continued until >90% of the dichioromethane was collected. The resulting suspension was then cooled to 20°C and aged for at least 30 min. prior to cooling to 0°C and aging for a further 60 min. The reaction mixture was then filtered and the product washed with additional 2-propanol, before drying at 50°C under vacuum to afford the title compound as an off-white crystalline solid.

The purity of the product was ascertained by HPLC, with identity confirmable by NMR. The yield was consistently >80% in several production runs.

PATENT

WO 2012015324

Example 1. Preparation of N-cyclohexyl-N-methyl-4-(pyridin-3yl)-lH-imidazole-l-carboxamide

C₈H₇N₃ C₁₅H_{1 1}N₃0₂ C₁₆H₂₀N₄O

MW 145,16 MW 265,27 MW 284,36

To a suspension of 3-(l/ -imidazol-4-yl)pyridine in tetrahydrofuran (THF) containing pyridine at 25°C was slowly added a solution of phenyl chloroformate in THF over 60 to 90 min. The resulting fine white suspension was then maintained at 25°C for at least 60 min. before the addition of N-methyl- -cyclohexylamine in a single portion, causing the suspension to thin and become yellow in colour. The reaction mixture was then stirred for 90 min. before filtering and washing the filter cake with additional THF. The mother liquors were then maintained at 25°C for at least 18 h, whereupon 65% of the volume of THF was distilled off under atmospheric pressure. The resulting solution was then diluted with 2-propanol and maintained at > 50°C for 10 min. prior to cooling down to 20°C. The resulting suspension was aged at 20°C for 15 min. prior to cooling to 0°C and aging for a further 60 min. The reaction mixture was then filtered and the product was washed with additional 2-propanol, before drying at 50°C under vacuum to afford the title compound as an off-white crystalline solid.

The purity of the product was ascertained by HPLC, with identity confirmable by NMR. The yield was consistently around 50% in several production runs.

Example 2. 3-(l-(cyclohexyl(methyl)carbamoyl-l//-imidazol-4-yl)pyridine 1 -oxide (compound A)

C₁₆H₂₀N₄O Ci6H2oN₄0₂

MW 284,36 MW 300,36

To a solution of N-cyclohexyl-N-methyl-4-(pyridin-3-yl)-lH-imidazole-l-carboxamide in dichloromethane at 25°C was added peracetic acid (38%; the concentration is not critical, and may be varied) in a single portion. The reaction mixture was then maintained at 25°C for at least 20 h, whereupon the reaction was washed four times with water. The dichloromethane solution was then filtered prior to diluting with 2-propanol. Dichloromethane (50%) was then distilled off under atmospheric pressure, whereupon, 2-propanol was charged at the same rate as the distillate was collected. The distillation was continued until >90% of the dichloromethane was collected. The resulting suspension was then cooled to 20°C and aged for at least 30 min. prior to cooling to 0°C and aging for a further 60 min. The reaction mixture was then filtered and the product washed with additional 2-propanol, before drying at 50°C under vacuum to afford the title compound as an off-white crystalline solid.

The purity of the product was ascertained by HPLC, with identity confirmable by NMR. The yield was consistently >80% in several production runs. It will be appreciated that this gives an overall yield of compound A many times greater than that achieved in the prior art.

In a further run of this synthesis, in a 2L reactor to a mixture of N-cyclohexyl-N-methyl-4-(pyridin-3-yl)-l H- imidazole-l-carboxamide (90 g, 317 mmol) and dichloromethane (1350 ml) was added peracetic acid (84 ml, 475 mmol). The reaction mixture was stirred at 25°C. Completion of the reaction was monitored by HPLC for the disappearance of N-cyclohexyl-N-methyl-4-(pyridin-3-yl)-lH- imidazole- 1-carboxamide. After reaction completion a solution of sodium metabisulfite (60.2 g, 317 mmol) in water (270ml) was added to the reaction mixture maintaining the temperature below 30°C. After phase separation the organic phase was washed with water. After phase separation the organic phase was concentrated at atmospheric pressure until 5 vol. Then solvent was swapped to isopropanol (1350 ml) and the suspension was cooled to 0°C during 4 hours and stirred at that temperature for 1 hour. The resulting solid was collected by filtration and was rinsed with water (270 ml) and isopropanol (270 ml) to afford a white crystalline solid in 84.8g (89%).

PATENT

WO 2010074588

Preparation of compound 362 a) N-cyclohexyl-N-methyl-4-(pyridin-3-yl)- 1 H-imidazole- 1 -carboxamide

To a stirred suspension of 3-( 1 H-imidazol-4-yl)pyridine dihydrochloride (1.745 g, 8 mmol) in a mixture of tetrahydrofuran (29 mL) and DMF (2.90 mL) was added potassium 2-methylpropan-2-olate (1.795 g, 16.0 mmol) and the mixture was refluxed for 30 minutes. The resulting brown suspension was cooled to room temperature and treated with pyridine (0.979 mL, 12 mmol) and N,N-dimethylpyridin-4-amine (0.098 g, 0.8 mmol), followed by the addition of cyclohexyl(methyl)carbamic chloride (1.476 g, 8.4 mmol). The reaction was heated to 90 ⁰C overnight, whereupon the mixture was diluted with water and extracted with ethyl acetate. The organic phase was dried (MgSO^) and filtered. After evaporation, the crude product was chromatographed over silica gel using a dichloromethane/methanol (9:1) mixture. Homogenous fractions were pooled and evaporated to leave a white powder, (160 mg, 7 %).

b) 3-( 1 -(cyclohexyl(methyl)carbamoyl)- 1 H-imidazol-4-yl)pyridine 1 -oxide

To a stirred solution of N-cyclohexyl-N-methyl-4-(pyridin-3-yl)-l H-imidazole- 1 -carboxamide (90 mg, 0.317 mmol) in chloroform (5 mL) was added 3-chlorobenzoρeroxoic acid (149 mg, 0.475 mmol) in one portion. The reaction was allowed to stir at room temperature for 20 h. TLC showed the reaction to be complete and the mixture was evaporated to dryness. The residue was triturated with ether and the resulting white crystals were filtered off and dried in air. Recrystallisation from hot isopropanol gave a white powder (46 mg, 46 %).

Structure and action

French newspaper Le Figaro has obtained Bial study protocol documents listing the the chemical name of BIA-10-2474 as 3-(1-(cyclohexyl(methyl)carbamoyl)-1H-imidazol-4-yl)pyridine 1-oxide.^[8] A Bial news release described BIA-10-2474 as “a long-acting inhibitor of FAAH”.^[9]

Fatty acid amide hydrolase (FAAH) is an enzyme which degrades endocannabinoid neurotransmitters like anandamide,^[10] which relieves pain and can affect eating and sleep patterns.^[11]^[12] FAAH inhibitors have been proposed for a range of nervous-system disorders including anxiety, alcoholism, pain and nausea.

The Portuguese pharmaceutical company Bial holds several patents on FAAH enzyme inhibitors.^[12]^[13]^[14]^[15]

No details of the preclinical testing of this molecule have been made public by the manufacturer Bial. However, the French newspaper Le Figaro has obtained and published an apparently legitimate copy of the full clinical trial protocol (BIA-102474-101).^[8] The protocol presents a summary of what appears to be a full package of pharmacodynamic, pharmacokinetic and toxicological studies that might be expected to support a first-in-man study, including safety pharmacology studies in two species (rat, dog) and repeated dose toxicity studies in four species (13 week sub-chronic studies in mouse, rat, dog and monkey). The summary presented however includes no assessment of the relevance of the animal species selected for study (that is, in terms of physiological and genetic similarities with humans and the mechanism of action of the study drug).

Of note, few adverse events were observed in any of the studies, with the 13-week oral No Observed Adverse Effect Level (NOAEL) varying between 10 mg/kg/day in mice to 75 mg/kg/day in monkeys. The authors suggest that these were the maximum doses tested in these studies, though it is not clear. The authors also report no effects of significance in the animal models used for the CNS safety pharmacology studies, which studied a dose of up to 300 mg/kg/day.^[8]

Notably absent from the protocol are calculations of receptor occupancy; predictions of in vivo ligand binding saturation levels; measures of target affinity; or assessment of the molecule’s activity in non-target tissues or non-target binding interactions as suggested by the European guidance for Phase I studies,^[16] assuming BIA 10-2474 could be considered ‘high risk’).^[8]

The trial protocol makes no reference to chimpanzee studies (only monkeys) which contradicts a previous statement to the media in which the French Health Minister stated that the drug had been tested on animals including chimpanzees.^[4]^[17] ^[18] Some experts had remarked that drug testing in chimpanzees was unlikely.^[19]

These findings provide no explanation for the type and severity of events observed in Rennes. In describing the rationale for the starting dose, the authors conclude that:

No target organ was identified during toxicology studies and few adverse clinical findings were observed at the highest dose tested. For the single ascending dose part [of the clinical trial], a starting dose of 0.25 mg was judged to be safe for a first-in-human administration. ^[8]

The protocol defines no starting dose for the multi-dose treatment groups, noting that this will be based on the outcome of the single dose portion of the trial (an approach known as adaptive trial design). The authors note that nonetheless, the starting dose will not exceed 33% of the maximum tolerated dose (MTD) identified in the single dose groups (or 33% of the maximum administered dose if the MTD is not reached).^[8]

Death and serious adverse events during phase I clinical trial

In July 2015 Biotrial, a contract research organization, began testing the drug in a human phase one clinical trial for the manufacturer. The study was approved by French regulatory authority, the Agence Nationale de Sécurité du Médicament (ANSM), on June 26, 2015, and by the Brest regional ethics committee on July 3, 2015.^[20] The trial commenced on July 9, 2015,^[21] in the city of Rennes, and recruited 128 healthy volunteers, both men and women aged 18 to 55. According to French authorities, the study employed a three-stage design with 90 of the volunteers having received the drug during the first two stages of the trial, with no serious adverse events being reported .^[17]^[20] Participants of the study were to receive €1,900 and, in turn, asked to stay at Biotrial’s facility for two weeks during which time they would take the drug for ten days and undergo tests.^[22]

In the third stage of the trial evaluating multiple doses, six male volunteers received doses by mouth, starting on 7 January 2016. The first volunteer was hospitalized at the Rennes University Hospital on January 10, became brain dead,^[17]^[23]^[24]^[25] and died on January 17.^[26] The other five men in the same dosage group were also hospitalized, in the period of January 10 through January 13^[27] four of them suffering injuries including deep hemorrhagic and necrotic lesions seen on brain MRI.^[7] The six men who were hospitalised were the group which received the highest dose.^[26] A neurologist at the University of Rennes Hospital Center, Professor Pierre-Gilles Edan, stated in a press conference with the French Minister for Health, that 3 of the 4 men who were displaying neurological symptoms “already have a severe enough clinical picture to fear that even in the best situation there will be an irreversible handicap” and were being given corticosteroids to control the inflammation.^[27] The sixth man from the group was not showing adverse effects but had been hospitalized for observation.^[25]^[28]^[29] Biotrial stopped the experiment on January 11, 2016.^[4]

No details of the trial have been made public by the manufacturer Bial. The study does not appear in searches of any of the key clinical trial registries, including EudraCT and ClinicalTrials.gov which would normally contain details of approved clinical studies.^[30]^[31]^[32]^[33] The trial protocol published by Le Figaro provides extensive detail on what was planned for the study, but many details of the key multi-dose part are not included and were to have been finalised at the conclusion of the single-dose part of the trial.^[8]

The French health minister Marisol Touraine called the event “an accident of exceptional gravity” and promised to investigate the matter.^[4] On January 18 it was reported authorities were investigating if a manufacturing or transport error might be involved.^[34]

Le Figaro posted a 96-page clinical study protocol for BIA 10-2474 that the French newspaper procured from an unnamed source.

According to the document, BIA 10-2474 is 3-(1-(cyclohexyl(methyl)carbamoyl)-1H-imidazol-4-yl)pyridine 1-oxide.

BIA 10-2474 “is designed to act as a long-active and reversible inhibitor of brain and peripheral FAAH,” notes the protocol. The compound “increases anandamide levels in the central nervous system and in peripheral tissues.”

The clinical trial protocol also notes that the company tested BIA 10-2474 on mice, rats, dogs, and monkeys for effects on the heart, kidneys, and gastrointestinal tract, among other pharmacological and toxicological evaluations.

09404-notw1-cliniccxd

Six men in a Phase I clinical trial were admitted to the University Hospital Center of Rennes, France, (shown here) because of adverse reactions.Six men in a Phase I clinical trial were admitted to the University Hospital Center of Rennes, France, (shown here) because of adverse reactions.

Credit: Mathieu Pattier/SIPA/Newscom

One man is dead and five men were hospitalized after participating in a Phase I clinical trial in Rennes, France

The clinical trial, conducted by the company Biotrial on behalf of the Portuguese pharmaceutical firm Bial, was evaluating a pain relief drug candidate called BIA 10-2474 that inhibits fatty acid amide hydrolase (FAAH) enzymes. Blocking these enzymes prevents them from breaking down cannabinoids in the brain, a family of compounds that includes the euphoria-inducing neurotransmitter anandamide and Δ⁹-tetrahydrocannabinol, the major psychoactive component of marijuana.

Phase I clinical trials are conducted to check a drug candidate’s safety profile in healthy, paid volunteers. In this case, the drug caused hemorrhagic and necrotic brain lesions in five out of six men in a group who received the highest doses of the drug, said Gilles Edan, a neurologist at the University Hospital Center of Rennes.

The most severely affected man was pronounced brain-dead after hospitalization and then died on Jan. 17. Four men remain in the hospital in stable condition. The only man in the high-dose group who had no adverse symptoms has been released from the hospital.

Clinical trials are an essential part of the drug development process. In order to get life-improving and life-saving medicines to patients, they first have to go through an extensive series of tests. Even before a drug makes it to Phase 1 testing, where its safety, dosage amount, and side effects are tested in a small group of humans, it will undergo testing in animals. As a result, it is not common for a medicine undergoing clinical tests to have a very serious adverse effect on a human. This makes you wonder what happened to a group of patients involved in a clinical study in Rennes, France.

According to news reports, a drug undergoing testing in a French clinic has left one person dead, two others with what may be permanent brain damage, and and two others critically ill. The drug has thus far been unnamed, but it appears to have been produced by the Portuguese company Bial. The French health minister has stated the drug acted on natural receptors found in the body known as endocannibinoids, which regulate mood and appetite. It did not contain cannabis or anything derived from it, as was originally reported. All six trial participants were administered the doses simultaneously.

The trial was being performed at Biotrial, a French-based firm that was formed in 1989 and has conducted thousands of trials. A message on the company’s website stated that they are working with health authorities to understand the cause of the accident, while extending thoughts to the patients and their families. Bial has disclosed the drug was a FAAH (fatty acid amide hydrolase) inhibitor, which is an enzyme produced in the brain and elsewhere that breaks down neurotransmitters called endocannabinoids. Two scientists from the Nottingham Medical School who have worked with FAAH tried over the weekend to try and identify the drug by examining a list of drugs Bial currently has in its pipeline. They believe the culprit is one identified by the codename BIA 10-2474. That same codename appeared on a recruitment form that was given to a volunteer, which was published in a French newspaper. Little more is known about it, and there does not appear to be any entry for it in clinical trial registries.

The French health ministry is reporting the six patients were all in good health prior to taking the oral medicine, which was administered to 90 volunteers. The trial recruited 128 individuals, and the remaining participants received a placebo. Health minister Marisol Touraine, describing the situation as a very serious accident, noted the patients were taking part in a trial in Brittany, Rennes involving a medicine developed by a “European laboratory”, refusing to comment further until additional information became available. She has also asked the Inspector General of Social Affairs to lead an investigation into the circumstances around the trial, which has obviously been suspended. She notes the drug had been tested on animals, including chimpanzees. France’s National Agency for Medicine and Health Products Safety approved the trial on in June 2015.

One thing we do know is that the trial was a Phase 1 clinical study that included 90 healthy volunteers. Regulations that oversee all clinical trials in Europe do attempt to minimize the risk associated with trials, but there is always a risk involved with administering an unapproved medicine to humans. At this time the chief neuroscientist at the hospital where the patients are being treated has said there is no known antidote for the drug.

The drug, administered to men between the ages of 28 and 49, was intended to treat mood disorders such as anxiety. While the men were administered varying doses, the patients who are hospitalized were taking the drug “regularly”.

Old 2006 case

While safety issues like this are rare, they are not unheard of. In 2006, a clinical trial in London left six men ill. All were taking part in a study testing a drug designed to fight auto-immune disease and leukemia. Within hours of taking the drug TGN1412, all experienced a serious reaction, were admitted to intensive care, and had to be treated for organ failure. Two became critically ill, with one eventually losing all of his fingers and toes. All were told they would have a higher risk of developing cancers or auto-immune diseases.

This of course led many to wonder about the future of trials, and whether the situation could happen again. The Duff Report, written in response to the TGN1412 trial, noted the medicine should have been tested in one person at a time. It also helped to put additional safety measures in place. The Medicines and Health Products Regulatory Agency (MHRA) now requires committees to look at pre-clinical data to determine the proper initial dose, and rules are in place to stop the trial if unintended reactions occur.

However, since patients can fall ill immediately after being administered a medication, certain risks will still exist.

The company that manufactured TGN1412, TeGenero Immuno Therapeutics, later went bankrupt. However the drug was later purchased by a Russian investor and renamed TABO8. TheraMAB, a Russian biotech company, then conducted a new trial of the drug in a much lower dose. A later Phase 2 study was started in patients with Rheumatoid Arthritis.

Other pharmaceutical companies, including Merck, Pfizer, Johnson & Johnson, Sanofi and Vernalis, have previously taken other FAAH inhibitors into clinical trials without experiencing such adverse events (e.g. respectively, MK-4409,^[35]^[36] PF-04457845, JNJ-42165279,^[37] SSR411298 and V158866.^[38]^[39] Related enzyme inhibitor compounds such as URB-597 and LY-2183240 have been sold illicitly as designer drugs,^[40]^[41] all without reports of this type of toxicity emerging, so the mechanism of the toxicity observed with BIA 10-2474 remains poorly understood.

Following the events in Rennes, Janssen announced that it was temporarily suspending dosing in two Phase II clinical trials with its own FAAH inhibitor JNJ-42165279, headlining the decision as “precautionary measure follows safety issue with different drug in class”. Janssen was emphatic that no serious adverse events had been reported in any of the clinical trials with JNJ-42165279 to date. The suspension is to remain in effect until more information is available about the BIA 10-2474 study.^[42]

References

1 “BRIEF-Bial says firmly committed to ensure wellbeing of test participants”. Reuters. 15 January 2016.
2 “BIA 10-2474”. Biocentury.com. Retrieved 2016-01-17.
3 “BIA 102474”. Adisinsight/springer.com. Retrieved 2016-01-17.
4 Adamson B (January 15, 2016). “Botched Drug Trial Leaves 1 Brain Dead, 5 in Hospital”. ABC, AP. Retrieved January 16, 2016.
5 Angeline Benoit,Makiko Kitamura (15 January 2016). “France Ties Brain-Dead Person to Tests of Bial-Portela Drug”. Bloomberg.com.
6 “France/Monde – Essai thérapeutique : 90 personnes ont pris la molécule”. Ledauphine.com. Retrieved 2016-01-17.
7 Enserink, Martin (2016). “More Details Emerge on Fateful French Drug Trial” (online). Science (January 16). Retrieved 16 January 2016.
8 “Drame de Rennes : le protocole de l’essai clinique en accusation”. sante.lefigaro.fr. Retrieved 2016-01-21.
9 “News Release – Phase I Clinical Trial Rennes”. http://www.bial.com. Retrieved 2016-01-21.
10 Debora Mackenzie. “Six in hospital after French pain relief drug trial goes wrong”. New Scientist.
11 “The Discovery and Development of Inhibitors of Fatty Acid Amide Hydrolase (FAAH)”. PubMed Central.
12 “Patent WO2015012708A1 – Imidazolecarboxamides and their use as faah inhibitors – Google Patents”. Google.com. Retrieved 2016-01-17.
13 “Patent WO2015016729A1 – Urea compounds and their use as faah enzyme inhibitors”. Google.com. Retrieved 2016-01-17.
14 “PT2014000052 UREA COMPOUNDS AND THEIR USE AS FAAH ENZYME INHIBITORS”. Patentscope.wipo.int. Retrieved 2016-01-17.
15 WO application 2015016729, Laszlo Erno KISS, Rita GUSMÃO DE NORONHA, Carla Patrícia ROSA DA COSTA PEREIRA, Rui PINTO, “Urea compounds and their use as faah enzyme inhibitors”, published Feb 5, 2015, assigned to BIAL
16″Strategies to identify and mitigate risks for first-in-human clinical trials with investigational medicinal products (CHMP/SWP/28367/07)” (PDF). European Medicines Agency. 1 September 2007. Retrieved 22 January 2016.
17 “Accident grave dans le cadre d’un essai clinique – Intervention de Marisol Touraine à Rennes”. Ministère des Affaires Sociales, de la Santé et des Droits des Femmes, France. 15 January 2016.
18Barbara Casassus (23 January 2016). “France investigates drug trial disaster” (PDF). The Lancet 387 (10016): 326. doi:10.1016/S0140-6736(16)00154-9.
19
“Expert reaction to French drug trial – reports of one patient dying and five others in hospital and of the Paris prosecutor’s office having opened an investigation into what happened”. Science Media Centre, London. 16 January 2016. Retrieved 21 January 2016.
20
“La survenue d’effets graves ayant entraîné l’hospitalisation de 6 patients, dont un en état de mort cérébrale, a conduit à l’arrêt prématuré d’un essai clinique du laboratoire BIAL – Point d’information”. Agence Nationale de Sécurité du Médicament, France (ANSM). 15 January 2016.
21
“Six hospitalized in Bial clinical trial in France”. BioWorld.com. Retrieved 2016-01-17.
22
Enserink M (January 16, 2016). “More details emerge on fateful French drug trial”. Science Magazine. Retrieved January 18, 2016.
23
“France clinical trial: 90 given drug, one man brain-dead”. BBC. January 15, 2016. Retrieved January 16, 2016.
24
“Ce que l’on sait de l’accident survenu lors d’un essai clinique à Rennes”, Le Monde, 15 January 2016
25
Blamont M (January 15, 2016). “French drug trial disaster leaves one brain dead, five injured”. Reuters. Retrieved January 16, 2016.
26
Clarisse Lucas, AFP (January 17, 2016). “Man dies after being left brain-dead in French drug trial”. Yahoo. Retrieved January 17, 2016.
27
“Accident “inédit” lors d’un essai clinique: un homme en état de mort cérébrale, cinq hospitalisés”. La Depeche. January 15, 2016. Retrieved January 18, 2016.
28
“France clinical trial: ‘No known antidote’ to drug”. BBC News. 15 January 2016. Retrieved 18 January 2016.
29
Enserink, Martin (2016). “What We Know So Far About the Clinical Trial Disaster in France” (online). Science (January 15). Retrieved 16 January 2016.
30
“EU Clinical Trials Register”. European Medicines Agency. Retrieved 20 January 2016.
31
“WHO International Clinical Trials Registry Platform”. World Health Organization. Retrieved 20 January 2016.
32
“ANSM – Répertoire public des essais cliniques de médicaments”. Agence Nationale de Sécurité du Médicament et des Produits de Santé, France. Retrieved 20 January 2016.
33
“ClinicalTrials.gov Registry”. U.S. National Institutes of Health. Retrieved 20 January 2016.
34
“Drug trial volunteer dies as ‘manufacturing error’ theory investigated”. The Independent. January 18, 2016. Retrieved January 18, 2016.
35
Chobanian; et al. (10 April 2014). “Discovery of MK-4409, a Novel Oxazole FAAH Inhibitor for the Treatment of Inflammatory and Neuropathic Pain”. ACS Med. Chem. Lett.
36
Merck (15 October 2009). “Merck Pipeline, Oct 2009” (PDF). Merck.
37
“Seven studies found for: jnj-42165279”. Clinicaltrials.gov. Retrieved 2016-01-19.
38
“2 studies found for: V158866”. Clinicaltrials.gov. Retrieved 2016-01-19.
39
Bisogno T, Maccarrone M. Latest advances in the discovery of fatty acid amide hydrolase inhibitors. Expert Opin Drug Discov. 2013 May;8(5):509-22. PMID 23488865 doi: 10.1517/17460441.2013.780021.
40
Shanks KG, Behonick GS, Dahn T, Terrell A. Identification of novel third-generation synthetic cannabinoids in products by ultra-performance liquid chromatography and time-of-flight mass spectrometry. J Anal Toxicol. 2013 Oct;37(8):517-25. PMID 23946450 doi: 10.1093/jat/bkt062.
41
Uchiyama N, Matsuda S, Kawamura M, Shimokawa Y, Kikura-Hanajiri R, Aritake K, Urade Y, Goda Y. Characterization of four new designer drugs, 5-chloro-NNEI, NNEI indazole analog, α-PHPP and α-POP, with 11 newly distributed designer drugs in illegal products. Forensic Sci Int. 2014 Oct;243:1-13. PMID 24769262 doi: 10.1016/j.forsciint.2014.03.013.

“Janssen Research & Development, LLC Voluntarily Suspends Dosing in Phase 2 Clinical Trials of Experimental Treatment for Mood Disorders”. Janssen.com. 17 January 2016. Retrieved 21 January 2016.

External links

Bial pipeline
Urea compounds and their use as faah enzyme inhibitors – Patent
Selection patent

WO2005073199A1 *	Jan 15, 2005	Aug 11, 2005	Aventis Pharma Gmbh	Indazole derivatives as inhibitors of hormone-sensitive lipases
WO2010074588A2	Dec 23, 2009	Jul 1, 2010	BIAL – PORTELA & Cª, S.A.	Pharmaceutical compounds
WO2012015324A1	Jul 28, 2011	Feb 2, 2012	Bial – Portela & Ca, S.A.	Process for the synthesis of substituted urea compounds
US4051252 *	Nov 24, 1975	Sep 27, 1977	Bayer Aktiengesellschaft	3-aminoindazole-1 and 2-carboxylic acid derivatives
US4331678 *	Jan 14, 1980	May 25, 1982	Fbc Limited	Carbamoyl pyrazole compounds and their pesticidal application
US4973588 *	Feb 10, 1989	Nov 27, 1990	Mitsui Petrochemical Industries, Ltd.	Imidazole derivatives having anti-hypoxia properties
US5578627 *	Oct 27, 1993	Nov 26, 1996	Toyama Chemical Co., Ltd.	1,2-benzoisoxazole derivative or its salt and brain-protecting agent comprising the same

BIA 10-2474

Systematic (IUPAC) name

3-(1-(cyclohexyl(methyl)carbamoyl)-1H-imidazol-4-yl)pyridine 1-oxide

Clinical data

Legal status

Investigational New Medicine

Routes of
administration

Oral

Identifiers

PubChem

CID: 46831476

Chemical data

Formula

C₁₆H₂₀N₄O₂

Molecular mass	300.36 g·mol⁻¹
SMILES O=C(N1C=C(C2=C[N+]([O-])=CC=C2)N=C1)N(C3CCCCC3)C

/////////

C1C(CCCC1)N(C)C(=O)n2cc(nc2)c3ccc[n+](c3)O

FDA´s Emerging Technology Applications Program – Draft Guidance

January 21, 2016 4:35 am / Leave a comment

FDA´s Emerging Technology Applications Program – Draft Guidance

The FDA recently published a draft guidance for industry on the “Advancement of Emerging Technology Applications”. The draft guidance provides recommendations to pharmaceutical companies interested in participating in a program involving the submission of CMC information containing emerging manufacturing (including testing, packaging and labeling, and quality control) technology to FDA. Find out more about the draft guidance for industry “Advancement of Emerging Technology Applications to Modernize the Pharmaceutical Manufacturing Base“..

http://www.gmp-compliance.org/enews_05164_FDA%B4s-Emerging-Technology-Applications-Program—Draft-Guidance_15455,15149,15153,Z-PDM_n.html

On December 23, 2015, the FDA published a draft guidance for industry “Advancement of Emerging Technology Applications to Modernize the Pharmaceutical Manufacturing Base“. Comments and suggestions regarding this draft document should be submitted within 60 days of publication.

The draft guidance provides recommendations to pharmaceutical companies interested in participating in a program involving the submission of CMC (chemistry, manufacturing, and controls) information containing emerging manufacturing (including testing, packaging and labeling operations, and quality control) technology to FDA.

The program is open for new drug applications (INDs), original or supplemental new drug application (NDA), abbreviated new drug application (ANDA), or biologic license application (BLA). It only affects the quality section of a submission (CMC and facility-related information).

The development of emerging manufacturing technology, like, for example, aseptic manufacturing facilities with highly automated systems and isolators, may lead to improved manufacturing, and therefore improved product quality and availability throughout a product´s lifecycle.

Pharmaceutical companies can submit questions and proposals about the use of these technologies to a group within CDER (Emerging Technology Team – ETT).

The draft guidance is a follow-on to the FDA guidance for industry “PAT – A Framework for Innovative Pharmaceutical Development, Manufacturing, and Quality Assurance” which describes the concept that quality cannot be tested into products. It should be built-in or should be present by design. Through the ETT, FDA intends to encourage the adoption of innovative approaches by leveraging existing resources of FDA to facilitate regulatory reviews of submissions.

Examples of emerging technology elements include an innovative or novel:

Product manufacturing technology, such as the dosage form;
Manufacturing process (e.g., design, scale-up, and/or commercial scale);
Testing technology.

Interested parties should submit a written meeting request to participate in the ETT program at least three months prior to the planned application (IND, ANDA, BLA, NDA) submission date. In addition to the items outlined in the FDA guidance “Formal Meetings Between the FDA and Sponsors or Applicants” the request should also include the following items:

A brief description of the proposed testing, process, and/or proposed technology;
A brief explanation why the proposed testing, process, and/or technology are substantially novel and unique;
A description of how the proposed testing and/or technology could modernize pharmaceutical manufacturing and thus improve product safety, identity, strength, quality, or purity;
A summary of the development plan and any perceived roadblocks to technical or regulatory implementation;
A timeline for submission.

The request should generally not exceed five pages and FDA expects to notify companies of its decision regarding acceptance into the program within 60 days of receipt of the request. Once accepted into the program, the participant can engage with ETT and CMC in accordance with existing meeting procedures and guidances (e.g. above mentioned FDA guidance on Formal Meetings).

For further information, please find all the details in the draft guidance “Advancement of Emerging Technology Applications to Modernize the Pharmaceutical Manufacturing Base“.

Lupin Ltd, Patent, Pitavastatin, WO2014203045

January 20, 2016 4:59 am / Leave a comment

Lupin Ltd, Patent, Pitavastatin, WO2014203045

A NOVEL, GREEN AND COST EFFECTIVE PROCESS FOR SYNTHESIS OF TERT-BUTYL (3R,5S)-6-OXO-3,5-DIHYDROXY-3,5-O-ISOPROPYLIDENE-HEXANOATE

ROY, Bhairabnath; (IN).
SINGH, Girij, Pal; (IN).
LATHI, Piyush, Suresh; (IN).
AGRAWAL, Manoj, Kunjabihari; (IN).
MITRA, Rangan; (IN).
TRIVEDI, Anurag; (IN).
PISE, Vijay, Sadashiv; (IN).
RUPANWAR, Manoj; (IN)

The present invention describes an eco-friendly and cost effective process for the synthesis of teri-butyl (3R,5S)-6-oxo-3,5-dihydroxy-3,5-0-isopropylidene-hexanoate [I]

PITAVASTATIN

TEXT

tert-b tyl (3R,5S)-6-oxo-3,5-dihydroxy-3,5-0-isopropylidene-hexanoate [I] [CAS No. 124752-23-4] is key intermediate for the preparation of statins such as Atorvastatin (Tetrahedron 63, 2007, 8124 -8134), Cerivastatin (Journal of Labeled Compounds and Radiopharmaceuticals, 49, 2006 311-319), Fluvastatin [WO2007125547; US 4739073], Pitavastatin [WO2007/132482; US2012/22102 Al, WO2010/77062 A2; WO2012/63254 Al ; EP 304063; Tetrahedron Letters, 1993, 34, 513 – 516; Bulletin of the Chemical Society of Japan, 1995, 68, 364 – 372] and Rosuvastatin [WO2007/125547 A2; WO2011/132172 Al ; EP 521471]. Statins are used for treatment of hypercholesterolemia, which reduces the LDL cholesterol levels by inhibiting activity of HMG-CoA reductase enzyme, which is involved in the synthesis of cholesterol in liver.

[I]

Compound [I] is generally obtained by various methods of oxidation of teri-butyl 2- ((4R,65)-6-(hydroxymethyl)-2,2-dimethyl-l,3-dioxan-4-yl)acetate [compound II] and are discussed in details hereinafter. In addition, various methods for synthesis of compound [II] are also elaborated below.

[II]

A) tert-butyl2-((4«,6.S)-6-(hydroxymethyl)-2,2-dimethyl-l,3-dioxan-4-yl)acetate

[compound II]

US patent Number 5278313 describes a process for synthesis of compound [II]

(Schemel). In the said process, (5)-methyl 4-chloro-3-hydroxybutanoate has been obtained in only 70% yield through whole cell enzymatic reduction of methyl 4-chloro-3- oxobutanoate, which has a necessity of special equipment such as fermenters as well as other microbial facilities such as sterile area, autoclaves, incubator for growing seed culture, etc.

(S)-mefhyl 4-chloro-3-hydroxybutanoate upon reaction with teri-butyl acetate in presence of LiHMDS or LDA at -78°C, yielded (S)-ieri-butyl 6-chloro-5-hydroxy-3- oxohexanoate, which was further transformed to corresponding diol through syn selective reduction in presence of methoxydiethyl borane/sodium borohydride at -78°C. The diol thus obtained was converted to compound [II] .

The overall yield for this process is low and required special equipment such as fermenters, etc and in addition to that, this process is not cost effective due to use of costly reagent such as methoxydiethyl borane.

Moreover, methoxydiethylborane is highly pyrophoric (Encyclopedia for organic synthesis, editor in chief L. Paquette; 2, 5304; Published by John and Wiley Sons;

Organic Process Research & Development 2006, 10, 1292-1295) and hence safety is a major concern.

Scheme 1

EP 1282719 B l (PCT application WO 01/85975 Al ) discloses a process for synthesis of compound ( R, 5S)-tert-bv y\ 3,5,6-trihydroxyhexanoate from (S)-tert-b tyl-5,6-dihydroxy-3-oxohexanoate through a) asymmetric hydrogenation in presence of a chiral catalyst e.g. di-mu-chlorobis-[(p-cymene)chlororuthenium(II)] along with an auxiliary such as (IS, 2S)-(+)-N- (4-toluenesulfonyl)-l ,2-diphenylethylenediamine as ligand, which gave desired product only in 70% diastereomeric excess (de); b) Whole cell enzymatic reduction of (S)-tert- butyl 5,6-dihydroxy-3-oxohexanoate to obtain compound (3R, 5S)-tert-bv y\ 3,5,6-trihydroxyhexanoate in 99% de (80% yield).

It is needless to mention that it has necessity of fermenter and other microbiological equipment (Scheme 2).

Moreover, conversion of (2>R,5S)-tert-bv y\ 6-acetoxy-3,5-dihydroxyhexanoate to tert-bv yl 2-((4R,65)-6-(acetoxymethyl)-2,2-dimethyl-l ,3-dioxan-4-yl)acetate was accomplished in only 25% yield and also required the flash chromatography for isolation of desired product.

Thus, overall yield for this process is poor and process is not operation friendly especially at large scale hence cannot be considered feasible for commercial manufacturing.

Scheme 2

EP1317440 Bl (PCT Application WO 02/06266 Al) has disclosed the process for synthesis of compound [II] from 6-chloro-2,4,6-trideoxy-D-erythro-hexose (Scheme 3) .

In the said patent application 6-chloro-2,4,6-trideoxy-D-erythro-hexose was converted to (4R, 65)-4-hydroxy-6-chloromethyl-tetrahydropyran-2one with excess of bromine in presence of potassium bicarbonate, which liberates environmentally undesired gas i.e. carbon dioxide.

Moreover, starting material i.e. 6-chloro-2,4,6-trideoxy-D-erythro-hexose is not commercially available and conversion efficiency of starting material at large scale towards (4R, 65)-4-hydroxy-6-chloromethyl-tetrahydropyran-2-one is only 67%.

Scheme 3

US Patent No. 6689591 B2 has demonstrated the whole cell enzymatic reduction of teri-butyl 6-chloro-3,5-dioxohexanoate to compound [II] (Scheme 4).

In the said process, whole cell enzymatic reduction is not specific; yield for desired product is only 34% and other partially reduced products are also obtained.

Hence, further purification is required for obtaining the desired compound. Thus, this process is not suitable for commercial scale.

Scheme 4

Tatsuya et al (Tetrahedron Letters; 34, 1993,513 – 516) has reported synthesis of compound [I] from derivative of L-tartatric acid (Scheme 5).

In the said process, tartaric acid di-i^‘sopropyl ester is doubly protected by tert-butyldimethylsilyl group, which was reacted with dianion of teri-butyl acetoacetate to give β, δ-diketo ester compound.

β,δ-diketo ester was reacted with 2 equivalent of diisobutylaluminium hydride (which is a pyrophoric reagent) to afford -hydroxy,8-keto ester in only 60% yield.

This process is not industrially viable as overall yield is very low and also because of use of costly and pyrophoric reagents/chemicals.

Scheme 5

US7205418 (PCT application WO03/053950A1) has described the process for synthesis of compound [II] from (S)-ieri-butyl-3,4-epoxybutanoate (Scheme 6).

The overall yield for this process is very low and moreover, it required the diastereomeric separation of teri-butyl 2-(6-(iodomethyl)-2-oxo-l,3-dioxan-4-yl)acetate by flash chromatography.

Since overall requirement of title compound is very high, any operation involving flash chromatography will tend to render the process commercially unviable.

Scheme 6

Fengali et al (Tetrahedron: Asymmetry 17; 2006; 2907-2913) has reported the process for synthesis of compound [II] from racemic epichlorohydrin (Scheme 7).

In this process, racemic epichlorohydrin was converted to corresponding nitrile intermediate through reaction with sodium cyanide; nitrile intermediate thus obtained was further resolved through lipase catalyzed stereo-selective esterification to obtain (5)-4-(benzyloxy)-3-hydroxybutanenitrile and (R)-l-(benzyloxy)-3-cyanopropan-2-yl acetate;

separation of desired product i.e. (S)-4-(benzyloxy)-3-hydroxybutanenitrile having 98% de (40% yield) was done by column chromatography.

Needless to mention a commodity chemical like compound [I] cannot be manufactured by such a laboratory method, which involved number of steps.

Scheme 7

Bode et al (Organic letters, 2002, 4, 619-621) has reported diastereomer- specific hydrolysis of 1,3-diol-acetonides (Scheme 8).

In this publication, duration of the reaction for diastereomer- specific hydrolysis of 1,3, diol-acetonides is reported to be 4 h, however, in our hand it was observed that hardly any reaction took place in 4 h, which made it non-reproducible.

In addition to that, separation of desired product is achieved by flash chromatography and it is needless to mention that any process which involved flash chromatography would render the process to be commercially unviable.

Hence, additional innovation needs to be put in for making the process industrially viable.

Scheme 8

CN 101613341A has reported the process for synthesis of compound [II] (Scheme

9).

In the same patent application tert-b tyl (S)-6-chloro-5-hydroxy-3-oxohexanoate was synthesized through Blaise condensation of (5)-4-chloro-3-hydorxy-butanenitrile with zinc enolate of tert butyl bromo acetate.

In the literature, synthesis of tert-bv yl (S)-6-chloro-5-hydroxy-3-oxohexanoate was reported through Blaise condensation of silyl protected (5)-4-chloro-3-(trimethylsilyl)oxy-butanenitrile with zinc enolate of tert butyl bromo acetate, in good yield (Synthesis 2004, 16, 2629-2632). Thus, protection of hydroxy group in (5)-4-chloro-3-hydorxy-butanenitrile is imperative.

In the said Chinese patent application, in claim 7, it was mentioned that solvent used for conversion of tert-bv yl (5)-6-chloro-5-hydroxy-3-oxohexanoate to ( R,5S)-tert-butyl 6-chloro-3,5-dihydroxyhexanoate is anyone or mixture of more than one from tetrahydrofuran, ether, methanol, ethanol, n-propanol, /so-propanol and ethylene glycol.

However, in enablement the only example using mixture of solvent was that of THF-methanol (Experimental section, Example 4: The preparation of (R,5)-6-chloro-3,5- dihydroxyhexanoate) and same outcome was expected in other individual or mixture of solvents.

Claim 8 of CN 101613341A mentioned that reduction was carried out by any one or mixture of more than one reducing agents such as sodium borohydride, potassium borohydride, lithium aluminum hydride, diethylmethoxy borane, triethyl borane and tributyl borane.

It implies that either any one of the reducing agents or a mixture of the same can be employed. From reaction mechanism it is very much clear that diethylmethoxy borane, triethyl borane and tributyl borane form the six membered complex between optically active hydroxyl and carbonyl group, which gets reduced by sodium borohydride, signifying that individually diethylmethoxy borane, triethyl borane and tributyl borane are not reducing agents

Moreover, in claims 12 and 13 (Experimental section, Example 4: The preparation of (R,S)-6-chloro-3,5-dihydroxyhexanoate), it is mentioned that reduction should be carried out in temperature range -80 °C to -60 °C, implying that reaction would not work beyond this temperature range i.e. it would work in the temperature window of -80 °C to -60 °C only.

Summarizing, the teachings of the application are not workable.

Scheme 9

Wolberg et al (Angewandte Chemie International Edition, 2000, 4306) has reported that diastereomeric excess for syn selective reduction using mixture of diethyl methoxy borane/sodium borohydride of compound [VI] gave 93% de for compound [VIII], which required further re-crystallization to obtain compound [VIII] in 99% de and 70% yield.

Thus, all the reported methods for stereo-selective hydride reduction of compound [VI] were achieved through mixture of trialkyl borane or diethyl methoxy borane & sodium borohydride in THF, at -78°C. As mentioned earlier, trialkyl borane or diethyl methoxy borane are pyrophoric in nature; in addition to that anhydrous THF is costly and moreover, reaction required large dilution.

Hence, there is need for developing efficient, environment friendly, cost effective and green process for stereo-selective reduction compound [VI].

B) The process of Oxidation of compound [II] to compound [I] has been discussed in following literature processes.

1) Swern oxidation (US4970313; Tetrahedron Letters, 1990, 2545

Synthetic Communications, 2003, 2275 – 2284).

2) Parrkh-Doering oxidation (J. Am. Chem. Soc, 1967, 89, 5505-5507)

3) TEMPO/NaOCl oxidization (EP2351762)

4) Trichloroisocyanuric acid/ TEMPO (CN 101747313A)

5) Oxidation of compound [II] to compound [I] through IBX [CN101475558A].

It would be evident that most of the reported methods are not “green” and

environmentally benign; none of the reported methods use molecular oxygen as oxidizing agent in presence of metal catalyst/co-catalyst.

Example 18: Process for synthesis of tert-butyl 2-((4R,6S)-6-formyl-2,2-dimethyl-l,3-dioxan-4-yl)acetate [I]

A reactor was charged with 1.1 g of copper (I) chloride and 10 mL of acetonitrile. 2-2′ Bipyridyl (156 mg) and TEMPO (156 mg) were added to the reactor under oxygen environment at 25°C. A solution of (6-Hydroxymethyl-2,2-dimethyl-[l,3]dioxan-4-yl)-acetic acid tert-butyl ester 2.6 g in 26 mL DCM was added dropwise over a period of 10 min into it. The reaction mass was stirred at 40°C and progress of reaction was monitored on GLC, which shows that 90% conversion for desired product.

Example 19: Process for synthesis of tert-butyl 2-((4R,6S)-6-formyl-2,2-dimethyl-l,3-dioxan-4-yl)acetate [I]

A reactor was charged with 1.1 g of copper (I) chloride and 10 mL of dichlorome thane. 2-2′ Bipyridyl (156 mg) and TEMPO (156 mg) were added to the reactor under oxygen environment at 25°C. A solution of (6-Hydroxymethyl-2,2-dimethyl-[l,3]dioxan-4-yl)-acetic acid tert-butyl ester 2.6 g in 26 mL DCM was added dropwise over a period of 10 min into it. The reaction mass was stirred at 40°C and progress of reaction was monitored on GLC, which shows that 90% conversion for desired product.

AUTHORS

SEE………https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2014203045&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=PCT+Biblio

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Breaking and Making of Olefins Simultaneously Using Ozonolysis: Application to the Synthesis of Useful Building Blocks and Macrocyclic Core of Solomonamides

January 19, 2016 6:43 am / Leave a comment

A simple and practical one-pot, two-directional approach to access olefinic esters through simultaneous breaking and making of olefins using ozonolysis of alkenyl aryl selenides is disclosed. The scope of the method with a variety of examples is demonstrated, and the end products obtained here are useful building blocks. As a direct application of the present method, the macrocyclic core of potent anti-inflammatory natural cyclic peptides, solomonamides, is synthesized.

Breaking and Making of Olefins Simultaneously Using Ozonolysis: Application to the Synthesis of Useful Building Blocks and Macrocyclic Core of Solomonamides

K. Kashinath, Santu Dhara, and D. Srinivasa Reddy^*

CSIR-National Chemical Laboratory, Division of Organic Chemistry, Dr. Homi Bhabha Road, Pune 411008, India

Org. Lett., 2015, 17 (9), pp 2090–2093

DOI: 10.1021/acs.orglett.5b00637

Publication Date (Web): April 14, 2015

*E-mail: ds.reddy@ncl.res.in.

http://pubs.acs.org/doi/abs/10.1021/acs.orglett.5b00637

http://pubs.acs.org/doi/suppl/10.1021/acs.orglett.5b00637/suppl_file/ol5b00637_si_001.pdf

GENERAL METHOD

Dr. D. Srinivasa Reddy

READ…….http://oneorganichemistoneday.blogspot.in/2015/02/dr-d-srinivasa-reddy.html

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